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Review of Ic variation Rc RRR and other parametersD Abraimov H W Weijers W D Markiewicz M Santos
J McCallister J Jaroszynski J Jiang J Lu V Toplosky B Jarvis S Carter Y L Viouchkov and D C Larbalestier all NHMFL
Quality Assurance procedure for 32T project
We are looking for compliance with our specification which includes
transport and geometrical properties of (Re)BCO tape using
minimum set of measurements
(Re)BCO coated conductor was purchased from SuperPower Inc
144 lengths 60 m or 110 m each
Comparison of 4K in- field Ic measured on short samples for conductors
from different manufacturers This work was supported in part by the US National Science Foundation under Grant No DMR-0654118 DMR-0923070 and the State of Florida
Special thanks to AMSC Fujikura SuNAM SuperOx for providing samples for testing
BIIabHigh Jc
B at 18o
to tape planebull One of the major limiting factors of coil
performance is sharp Jc(Q) dependence in (Re)BCO bull The minimum Ic for 32 T coil design occurs at 18o
critical angle between tape plane and magnetic field of 17 T
Origins of specification for (Re)BCO conductor
Xu A et al Superconducting Science and Technology 23 014003 (2010)
BIIab
Restriction on Ic
bull Tape is being delivered in 110 or 60 m lengths making joints resistance critical
bull RRRgt50 for low resistance of stabilizer in case of quench
Dimensionsbull Cu stabilizer layer should be uniform through
length and width of the tape to provide mechanical stability between pancake windings and get uniform heat propagation
bull Tape width should be uniform to avoid variations in Ic and mechanical properties difficulties in coil manufacturing
17 T
Other transport properties
Property of tape from the specification Value Units
Minimum Ic at 42 K extrapolated to 17 T from Ic(B) measured at 18o angle gt256 A
n from V~I n fit gt25 -Joints resistance measurements le230 mWmiddotcm2
Residual Resistivity Ratio of Cu (42 to 300 K) gt50 -
Final conductor width 410 plusmn 005 mm
Final conductor Thickness le0170 mm
Cu Stabilizer Cross-sectional Area 042 plusmn 001 mm 2
Substrate cross-sectional Area 020 plusmn 001 mm 2
Ag layer thickness 20 plusmn 05 mm
(Re)BCO conductor specification(short list)
Current biasing two Sorensen power supplies
bull up to 1400 Abull Analog connection
Current monitor Keithley 2000Voltage measurement Keithley 2184AMagnet power supply Lake Shore LS 622
LabView based program for automatic B and Ibias sweeping and Ic calculation
Ic testing system for 32 T tape characterization
Oxford InstrumentsSuperconducting 135 T (42K) magnet
sample holder
Other techniquesroutine QA tests
Nikon iNexiv VMA-2520 microscope
Final conductor width Surface conditionThickness profiles
Vibromet 2
Preparation cross-sections
SEM visualization with Zeiss 1540 XB Cross beam
Olympus Microscope BX41M-LED
Total conductor thicknessCu Stabilizer cross‐sectional areaSubstrate cross-sectional area
Simplimet 3000Ag thicknessReBCO uniformityab-plane orientation
Transport measurements of Rc Ic of lap joints in LN self field
Additional techniques used for study properties of ReBCO tapes
bull 16 T Quantum design PPMS for measuring in- field
variable temperature angular dependence of Ic and R(T)
bull Rotator with split coil electromagnet 1T 77K for
measuring angular dependence of Ic in full width tapes
bull YateStar system for measuring distribution of transport
critical current at 77K 08T 50 75 100 125 150 175 200 225 250 275 3000
5
10
15
20
25
30
35
40
45
50
55
60
65
70
T=77K B=1 T
SP125 inner SuNAM
I c A
degree
-30 0 30 60 90 120 150 180 210
10
1T 2T 4T 8T 12T 16T
J c M
Ac
m2
degree904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
RR
(30
0K
)
Temperature (K)
Contact resistance of lap joints
Contact resistance arranged by SP process run numberSmall spread within each run but has large difference between some runs
Maximum average160 nW cm2
Peak maximum230 nW cm2
Measurements done on standard lap joints with 80 mm overlap80 mm
32T spec
M3-1033M3-1062have low Ic (4K) and high joint resistance
T=77K SF
0 20 40 60 80 1000
100
200
300
40010
22-1
1024
-310
28-1
1029
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
1038
1038
1038
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4
1048
-210
48-2 10
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-2 1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-2 1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2 11
11-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2 21
7-2
217-
421
8-2 21
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
M3
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
M4
Measurements of in-field critical currents at fixed orientation
Ic(42K18oB)
Typical Ic(B) dependence measured as field rises and decreases and current rises and decreases (LabView screenshot)
No hysteresis and no damage during field sweep
SP62 inner part of length (N5)Bias current measured from 200 A DI=2 AThis field dependence was measured during 39 minDepending on Ic values field dependence takes 34 min ndash 40 min
8 9 10 11 12 13 14 15 16 17
250
300
350
400
450
500
550600650700
UP SP60 inner Down SP60 inner UP SP60 out Down SP60 out UP SP61 out Down SP61 out UP SP61 inner Down SP61 inner UP SP62 inner Down SP62 inner UP SP62 out Down SP62 out UP SP63 out Down SP63 out
I c A
B T
Representative selection of Ic(B) curves measured at 42 K with 18o between sample plane and B
Orange horizontal line represents 256A minimum specified at 17T
B
Most of measured samples have Ic gt 256 A
No hysteresis in increasing and decreasing field These data have tight fit to Ic~B-a
I
60 80 100 120 140 160 180 2000
50
100
150
200
250
300
350
400
450
500
550
600
650
700
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700 outer I
c(4K17T18o)
inner Ic(4K17T18o)
outer Ic(77KSF)
inner Ic(77KSF)
SP Min Ic(77KSF) 32T spec
I c a
t 77
K S
F A
I c a
t 18
o 4
2K
ext
rap
ola
ted
to 1
7T
A
Tape
Progress in Ic measurements SP60 ndash SP207 Data arranged by NHMFL numbers ndash delivery time line
Tapes SP65 66 79 80 were sent for developing winding technique
144 lengths 60 m or 110 m each
100 110 120 130 140 150 160 170 1800
10
20
30
40
50
Nu
mb
er
of s
am
ple
s
Ic(SF77K) A
Histogram of Ic measured at 77K SF
ltIcgt=130 A SD=105
150 200 250 300 350 400 450 500 550 6000
5
10
15
20
25
30
35
Nu
mb
er
of s
am
ple
s
Ic(4K18o17T) A
Histogram for Ic measured at 42 K 17 T 18deg
Before we were dealing mostlywith this conductor produced with M3 machine
Now we are receiving more M4 tapes suitable for top and bottom parts of the magnet
M4 16 Ic variability
M3 16 of Ic variability
0 20 40 60 80 100 120 1400
50
100
150
200
250
300
350
400
450
500
550
600
650
700
75010
2910
38 1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-1 1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4 10
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-3 1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4 1062
-410
63-2
1063
-210
63-2 10
67-2
1071
-210
72-3 10
78-2
1078
-2 1078
-210
78-2
1084
-210
88-2
1088
-210
89-2
1094
-210
94-2
1111
-211
11-2
1115
-218
0-3
180-
418
2-2
182-
218
2-4
195-
2 195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2 218-
221
8-2 21
8-2
218-
221
9-2
219-
221
9-2
219-
221
9-2
219-
2 219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
2 246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
7-2
247-
2
ltIc(4K17T18o)gt
Inner Ic(4K17T18o)
Outer Ic(4K17T18o)
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4passed with large margin
M3
Ic(4K17T18o) data arranged as ascending SuperPower run number (we assume it as time line for each M3 M4 machine)
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
=159
=105
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
BIIabHigh Jc
B at 18o
to tape planebull One of the major limiting factors of coil
performance is sharp Jc(Q) dependence in (Re)BCO bull The minimum Ic for 32 T coil design occurs at 18o
critical angle between tape plane and magnetic field of 17 T
Origins of specification for (Re)BCO conductor
Xu A et al Superconducting Science and Technology 23 014003 (2010)
BIIab
Restriction on Ic
bull Tape is being delivered in 110 or 60 m lengths making joints resistance critical
bull RRRgt50 for low resistance of stabilizer in case of quench
Dimensionsbull Cu stabilizer layer should be uniform through
length and width of the tape to provide mechanical stability between pancake windings and get uniform heat propagation
bull Tape width should be uniform to avoid variations in Ic and mechanical properties difficulties in coil manufacturing
17 T
Other transport properties
Property of tape from the specification Value Units
Minimum Ic at 42 K extrapolated to 17 T from Ic(B) measured at 18o angle gt256 A
n from V~I n fit gt25 -Joints resistance measurements le230 mWmiddotcm2
Residual Resistivity Ratio of Cu (42 to 300 K) gt50 -
Final conductor width 410 plusmn 005 mm
Final conductor Thickness le0170 mm
Cu Stabilizer Cross-sectional Area 042 plusmn 001 mm 2
Substrate cross-sectional Area 020 plusmn 001 mm 2
Ag layer thickness 20 plusmn 05 mm
(Re)BCO conductor specification(short list)
Current biasing two Sorensen power supplies
bull up to 1400 Abull Analog connection
Current monitor Keithley 2000Voltage measurement Keithley 2184AMagnet power supply Lake Shore LS 622
LabView based program for automatic B and Ibias sweeping and Ic calculation
Ic testing system for 32 T tape characterization
Oxford InstrumentsSuperconducting 135 T (42K) magnet
sample holder
Other techniquesroutine QA tests
Nikon iNexiv VMA-2520 microscope
Final conductor width Surface conditionThickness profiles
Vibromet 2
Preparation cross-sections
SEM visualization with Zeiss 1540 XB Cross beam
Olympus Microscope BX41M-LED
Total conductor thicknessCu Stabilizer cross‐sectional areaSubstrate cross-sectional area
Simplimet 3000Ag thicknessReBCO uniformityab-plane orientation
Transport measurements of Rc Ic of lap joints in LN self field
Additional techniques used for study properties of ReBCO tapes
bull 16 T Quantum design PPMS for measuring in- field
variable temperature angular dependence of Ic and R(T)
bull Rotator with split coil electromagnet 1T 77K for
measuring angular dependence of Ic in full width tapes
bull YateStar system for measuring distribution of transport
critical current at 77K 08T 50 75 100 125 150 175 200 225 250 275 3000
5
10
15
20
25
30
35
40
45
50
55
60
65
70
T=77K B=1 T
SP125 inner SuNAM
I c A
degree
-30 0 30 60 90 120 150 180 210
10
1T 2T 4T 8T 12T 16T
J c M
Ac
m2
degree904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
RR
(30
0K
)
Temperature (K)
Contact resistance of lap joints
Contact resistance arranged by SP process run numberSmall spread within each run but has large difference between some runs
Maximum average160 nW cm2
Peak maximum230 nW cm2
Measurements done on standard lap joints with 80 mm overlap80 mm
32T spec
M3-1033M3-1062have low Ic (4K) and high joint resistance
T=77K SF
0 20 40 60 80 1000
100
200
300
40010
22-1
1024
-310
28-1
1029
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
1038
1038
1038
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4
1048
-210
48-2 10
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-2 1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-2 1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2 11
11-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2 21
7-2
217-
421
8-2 21
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
M3
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
M4
Measurements of in-field critical currents at fixed orientation
Ic(42K18oB)
Typical Ic(B) dependence measured as field rises and decreases and current rises and decreases (LabView screenshot)
No hysteresis and no damage during field sweep
SP62 inner part of length (N5)Bias current measured from 200 A DI=2 AThis field dependence was measured during 39 minDepending on Ic values field dependence takes 34 min ndash 40 min
8 9 10 11 12 13 14 15 16 17
250
300
350
400
450
500
550600650700
UP SP60 inner Down SP60 inner UP SP60 out Down SP60 out UP SP61 out Down SP61 out UP SP61 inner Down SP61 inner UP SP62 inner Down SP62 inner UP SP62 out Down SP62 out UP SP63 out Down SP63 out
I c A
B T
Representative selection of Ic(B) curves measured at 42 K with 18o between sample plane and B
Orange horizontal line represents 256A minimum specified at 17T
B
Most of measured samples have Ic gt 256 A
No hysteresis in increasing and decreasing field These data have tight fit to Ic~B-a
I
60 80 100 120 140 160 180 2000
50
100
150
200
250
300
350
400
450
500
550
600
650
700
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700 outer I
c(4K17T18o)
inner Ic(4K17T18o)
outer Ic(77KSF)
inner Ic(77KSF)
SP Min Ic(77KSF) 32T spec
I c a
t 77
K S
F A
I c a
t 18
o 4
2K
ext
rap
ola
ted
to 1
7T
A
Tape
Progress in Ic measurements SP60 ndash SP207 Data arranged by NHMFL numbers ndash delivery time line
Tapes SP65 66 79 80 were sent for developing winding technique
144 lengths 60 m or 110 m each
100 110 120 130 140 150 160 170 1800
10
20
30
40
50
Nu
mb
er
of s
am
ple
s
Ic(SF77K) A
Histogram of Ic measured at 77K SF
ltIcgt=130 A SD=105
150 200 250 300 350 400 450 500 550 6000
5
10
15
20
25
30
35
Nu
mb
er
of s
am
ple
s
Ic(4K18o17T) A
Histogram for Ic measured at 42 K 17 T 18deg
Before we were dealing mostlywith this conductor produced with M3 machine
Now we are receiving more M4 tapes suitable for top and bottom parts of the magnet
M4 16 Ic variability
M3 16 of Ic variability
0 20 40 60 80 100 120 1400
50
100
150
200
250
300
350
400
450
500
550
600
650
700
75010
2910
38 1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-1 1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4 10
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-3 1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4 1062
-410
63-2
1063
-210
63-2 10
67-2
1071
-210
72-3 10
78-2
1078
-2 1078
-210
78-2
1084
-210
88-2
1088
-210
89-2
1094
-210
94-2
1111
-211
11-2
1115
-218
0-3
180-
418
2-2
182-
218
2-4
195-
2 195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2 218-
221
8-2 21
8-2
218-
221
9-2
219-
221
9-2
219-
221
9-2
219-
2 219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
2 246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
7-2
247-
2
ltIc(4K17T18o)gt
Inner Ic(4K17T18o)
Outer Ic(4K17T18o)
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4passed with large margin
M3
Ic(4K17T18o) data arranged as ascending SuperPower run number (we assume it as time line for each M3 M4 machine)
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
=159
=105
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
Property of tape from the specification Value Units
Minimum Ic at 42 K extrapolated to 17 T from Ic(B) measured at 18o angle gt256 A
n from V~I n fit gt25 -Joints resistance measurements le230 mWmiddotcm2
Residual Resistivity Ratio of Cu (42 to 300 K) gt50 -
Final conductor width 410 plusmn 005 mm
Final conductor Thickness le0170 mm
Cu Stabilizer Cross-sectional Area 042 plusmn 001 mm 2
Substrate cross-sectional Area 020 plusmn 001 mm 2
Ag layer thickness 20 plusmn 05 mm
(Re)BCO conductor specification(short list)
Current biasing two Sorensen power supplies
bull up to 1400 Abull Analog connection
Current monitor Keithley 2000Voltage measurement Keithley 2184AMagnet power supply Lake Shore LS 622
LabView based program for automatic B and Ibias sweeping and Ic calculation
Ic testing system for 32 T tape characterization
Oxford InstrumentsSuperconducting 135 T (42K) magnet
sample holder
Other techniquesroutine QA tests
Nikon iNexiv VMA-2520 microscope
Final conductor width Surface conditionThickness profiles
Vibromet 2
Preparation cross-sections
SEM visualization with Zeiss 1540 XB Cross beam
Olympus Microscope BX41M-LED
Total conductor thicknessCu Stabilizer cross‐sectional areaSubstrate cross-sectional area
Simplimet 3000Ag thicknessReBCO uniformityab-plane orientation
Transport measurements of Rc Ic of lap joints in LN self field
Additional techniques used for study properties of ReBCO tapes
bull 16 T Quantum design PPMS for measuring in- field
variable temperature angular dependence of Ic and R(T)
bull Rotator with split coil electromagnet 1T 77K for
measuring angular dependence of Ic in full width tapes
bull YateStar system for measuring distribution of transport
critical current at 77K 08T 50 75 100 125 150 175 200 225 250 275 3000
5
10
15
20
25
30
35
40
45
50
55
60
65
70
T=77K B=1 T
SP125 inner SuNAM
I c A
degree
-30 0 30 60 90 120 150 180 210
10
1T 2T 4T 8T 12T 16T
J c M
Ac
m2
degree904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
RR
(30
0K
)
Temperature (K)
Contact resistance of lap joints
Contact resistance arranged by SP process run numberSmall spread within each run but has large difference between some runs
Maximum average160 nW cm2
Peak maximum230 nW cm2
Measurements done on standard lap joints with 80 mm overlap80 mm
32T spec
M3-1033M3-1062have low Ic (4K) and high joint resistance
T=77K SF
0 20 40 60 80 1000
100
200
300
40010
22-1
1024
-310
28-1
1029
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
1038
1038
1038
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4
1048
-210
48-2 10
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-2 1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-2 1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2 11
11-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2 21
7-2
217-
421
8-2 21
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
M3
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
M4
Measurements of in-field critical currents at fixed orientation
Ic(42K18oB)
Typical Ic(B) dependence measured as field rises and decreases and current rises and decreases (LabView screenshot)
No hysteresis and no damage during field sweep
SP62 inner part of length (N5)Bias current measured from 200 A DI=2 AThis field dependence was measured during 39 minDepending on Ic values field dependence takes 34 min ndash 40 min
8 9 10 11 12 13 14 15 16 17
250
300
350
400
450
500
550600650700
UP SP60 inner Down SP60 inner UP SP60 out Down SP60 out UP SP61 out Down SP61 out UP SP61 inner Down SP61 inner UP SP62 inner Down SP62 inner UP SP62 out Down SP62 out UP SP63 out Down SP63 out
I c A
B T
Representative selection of Ic(B) curves measured at 42 K with 18o between sample plane and B
Orange horizontal line represents 256A minimum specified at 17T
B
Most of measured samples have Ic gt 256 A
No hysteresis in increasing and decreasing field These data have tight fit to Ic~B-a
I
60 80 100 120 140 160 180 2000
50
100
150
200
250
300
350
400
450
500
550
600
650
700
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700 outer I
c(4K17T18o)
inner Ic(4K17T18o)
outer Ic(77KSF)
inner Ic(77KSF)
SP Min Ic(77KSF) 32T spec
I c a
t 77
K S
F A
I c a
t 18
o 4
2K
ext
rap
ola
ted
to 1
7T
A
Tape
Progress in Ic measurements SP60 ndash SP207 Data arranged by NHMFL numbers ndash delivery time line
Tapes SP65 66 79 80 were sent for developing winding technique
144 lengths 60 m or 110 m each
100 110 120 130 140 150 160 170 1800
10
20
30
40
50
Nu
mb
er
of s
am
ple
s
Ic(SF77K) A
Histogram of Ic measured at 77K SF
ltIcgt=130 A SD=105
150 200 250 300 350 400 450 500 550 6000
5
10
15
20
25
30
35
Nu
mb
er
of s
am
ple
s
Ic(4K18o17T) A
Histogram for Ic measured at 42 K 17 T 18deg
Before we were dealing mostlywith this conductor produced with M3 machine
Now we are receiving more M4 tapes suitable for top and bottom parts of the magnet
M4 16 Ic variability
M3 16 of Ic variability
0 20 40 60 80 100 120 1400
50
100
150
200
250
300
350
400
450
500
550
600
650
700
75010
2910
38 1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-1 1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4 10
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-3 1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4 1062
-410
63-2
1063
-210
63-2 10
67-2
1071
-210
72-3 10
78-2
1078
-2 1078
-210
78-2
1084
-210
88-2
1088
-210
89-2
1094
-210
94-2
1111
-211
11-2
1115
-218
0-3
180-
418
2-2
182-
218
2-4
195-
2 195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2 218-
221
8-2 21
8-2
218-
221
9-2
219-
221
9-2
219-
221
9-2
219-
2 219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
2 246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
7-2
247-
2
ltIc(4K17T18o)gt
Inner Ic(4K17T18o)
Outer Ic(4K17T18o)
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4passed with large margin
M3
Ic(4K17T18o) data arranged as ascending SuperPower run number (we assume it as time line for each M3 M4 machine)
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
=159
=105
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
Current biasing two Sorensen power supplies
bull up to 1400 Abull Analog connection
Current monitor Keithley 2000Voltage measurement Keithley 2184AMagnet power supply Lake Shore LS 622
LabView based program for automatic B and Ibias sweeping and Ic calculation
Ic testing system for 32 T tape characterization
Oxford InstrumentsSuperconducting 135 T (42K) magnet
sample holder
Other techniquesroutine QA tests
Nikon iNexiv VMA-2520 microscope
Final conductor width Surface conditionThickness profiles
Vibromet 2
Preparation cross-sections
SEM visualization with Zeiss 1540 XB Cross beam
Olympus Microscope BX41M-LED
Total conductor thicknessCu Stabilizer cross‐sectional areaSubstrate cross-sectional area
Simplimet 3000Ag thicknessReBCO uniformityab-plane orientation
Transport measurements of Rc Ic of lap joints in LN self field
Additional techniques used for study properties of ReBCO tapes
bull 16 T Quantum design PPMS for measuring in- field
variable temperature angular dependence of Ic and R(T)
bull Rotator with split coil electromagnet 1T 77K for
measuring angular dependence of Ic in full width tapes
bull YateStar system for measuring distribution of transport
critical current at 77K 08T 50 75 100 125 150 175 200 225 250 275 3000
5
10
15
20
25
30
35
40
45
50
55
60
65
70
T=77K B=1 T
SP125 inner SuNAM
I c A
degree
-30 0 30 60 90 120 150 180 210
10
1T 2T 4T 8T 12T 16T
J c M
Ac
m2
degree904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
RR
(30
0K
)
Temperature (K)
Contact resistance of lap joints
Contact resistance arranged by SP process run numberSmall spread within each run but has large difference between some runs
Maximum average160 nW cm2
Peak maximum230 nW cm2
Measurements done on standard lap joints with 80 mm overlap80 mm
32T spec
M3-1033M3-1062have low Ic (4K) and high joint resistance
T=77K SF
0 20 40 60 80 1000
100
200
300
40010
22-1
1024
-310
28-1
1029
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
1038
1038
1038
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4
1048
-210
48-2 10
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-2 1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-2 1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2 11
11-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2 21
7-2
217-
421
8-2 21
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
M3
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
M4
Measurements of in-field critical currents at fixed orientation
Ic(42K18oB)
Typical Ic(B) dependence measured as field rises and decreases and current rises and decreases (LabView screenshot)
No hysteresis and no damage during field sweep
SP62 inner part of length (N5)Bias current measured from 200 A DI=2 AThis field dependence was measured during 39 minDepending on Ic values field dependence takes 34 min ndash 40 min
8 9 10 11 12 13 14 15 16 17
250
300
350
400
450
500
550600650700
UP SP60 inner Down SP60 inner UP SP60 out Down SP60 out UP SP61 out Down SP61 out UP SP61 inner Down SP61 inner UP SP62 inner Down SP62 inner UP SP62 out Down SP62 out UP SP63 out Down SP63 out
I c A
B T
Representative selection of Ic(B) curves measured at 42 K with 18o between sample plane and B
Orange horizontal line represents 256A minimum specified at 17T
B
Most of measured samples have Ic gt 256 A
No hysteresis in increasing and decreasing field These data have tight fit to Ic~B-a
I
60 80 100 120 140 160 180 2000
50
100
150
200
250
300
350
400
450
500
550
600
650
700
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700 outer I
c(4K17T18o)
inner Ic(4K17T18o)
outer Ic(77KSF)
inner Ic(77KSF)
SP Min Ic(77KSF) 32T spec
I c a
t 77
K S
F A
I c a
t 18
o 4
2K
ext
rap
ola
ted
to 1
7T
A
Tape
Progress in Ic measurements SP60 ndash SP207 Data arranged by NHMFL numbers ndash delivery time line
Tapes SP65 66 79 80 were sent for developing winding technique
144 lengths 60 m or 110 m each
100 110 120 130 140 150 160 170 1800
10
20
30
40
50
Nu
mb
er
of s
am
ple
s
Ic(SF77K) A
Histogram of Ic measured at 77K SF
ltIcgt=130 A SD=105
150 200 250 300 350 400 450 500 550 6000
5
10
15
20
25
30
35
Nu
mb
er
of s
am
ple
s
Ic(4K18o17T) A
Histogram for Ic measured at 42 K 17 T 18deg
Before we were dealing mostlywith this conductor produced with M3 machine
Now we are receiving more M4 tapes suitable for top and bottom parts of the magnet
M4 16 Ic variability
M3 16 of Ic variability
0 20 40 60 80 100 120 1400
50
100
150
200
250
300
350
400
450
500
550
600
650
700
75010
2910
38 1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-1 1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4 10
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-3 1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4 1062
-410
63-2
1063
-210
63-2 10
67-2
1071
-210
72-3 10
78-2
1078
-2 1078
-210
78-2
1084
-210
88-2
1088
-210
89-2
1094
-210
94-2
1111
-211
11-2
1115
-218
0-3
180-
418
2-2
182-
218
2-4
195-
2 195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2 218-
221
8-2 21
8-2
218-
221
9-2
219-
221
9-2
219-
221
9-2
219-
2 219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
2 246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
7-2
247-
2
ltIc(4K17T18o)gt
Inner Ic(4K17T18o)
Outer Ic(4K17T18o)
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4passed with large margin
M3
Ic(4K17T18o) data arranged as ascending SuperPower run number (we assume it as time line for each M3 M4 machine)
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
=159
=105
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
Other techniquesroutine QA tests
Nikon iNexiv VMA-2520 microscope
Final conductor width Surface conditionThickness profiles
Vibromet 2
Preparation cross-sections
SEM visualization with Zeiss 1540 XB Cross beam
Olympus Microscope BX41M-LED
Total conductor thicknessCu Stabilizer cross‐sectional areaSubstrate cross-sectional area
Simplimet 3000Ag thicknessReBCO uniformityab-plane orientation
Transport measurements of Rc Ic of lap joints in LN self field
Additional techniques used for study properties of ReBCO tapes
bull 16 T Quantum design PPMS for measuring in- field
variable temperature angular dependence of Ic and R(T)
bull Rotator with split coil electromagnet 1T 77K for
measuring angular dependence of Ic in full width tapes
bull YateStar system for measuring distribution of transport
critical current at 77K 08T 50 75 100 125 150 175 200 225 250 275 3000
5
10
15
20
25
30
35
40
45
50
55
60
65
70
T=77K B=1 T
SP125 inner SuNAM
I c A
degree
-30 0 30 60 90 120 150 180 210
10
1T 2T 4T 8T 12T 16T
J c M
Ac
m2
degree904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
RR
(30
0K
)
Temperature (K)
Contact resistance of lap joints
Contact resistance arranged by SP process run numberSmall spread within each run but has large difference between some runs
Maximum average160 nW cm2
Peak maximum230 nW cm2
Measurements done on standard lap joints with 80 mm overlap80 mm
32T spec
M3-1033M3-1062have low Ic (4K) and high joint resistance
T=77K SF
0 20 40 60 80 1000
100
200
300
40010
22-1
1024
-310
28-1
1029
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
1038
1038
1038
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4
1048
-210
48-2 10
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-2 1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-2 1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2 11
11-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2 21
7-2
217-
421
8-2 21
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
M3
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
M4
Measurements of in-field critical currents at fixed orientation
Ic(42K18oB)
Typical Ic(B) dependence measured as field rises and decreases and current rises and decreases (LabView screenshot)
No hysteresis and no damage during field sweep
SP62 inner part of length (N5)Bias current measured from 200 A DI=2 AThis field dependence was measured during 39 minDepending on Ic values field dependence takes 34 min ndash 40 min
8 9 10 11 12 13 14 15 16 17
250
300
350
400
450
500
550600650700
UP SP60 inner Down SP60 inner UP SP60 out Down SP60 out UP SP61 out Down SP61 out UP SP61 inner Down SP61 inner UP SP62 inner Down SP62 inner UP SP62 out Down SP62 out UP SP63 out Down SP63 out
I c A
B T
Representative selection of Ic(B) curves measured at 42 K with 18o between sample plane and B
Orange horizontal line represents 256A minimum specified at 17T
B
Most of measured samples have Ic gt 256 A
No hysteresis in increasing and decreasing field These data have tight fit to Ic~B-a
I
60 80 100 120 140 160 180 2000
50
100
150
200
250
300
350
400
450
500
550
600
650
700
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700 outer I
c(4K17T18o)
inner Ic(4K17T18o)
outer Ic(77KSF)
inner Ic(77KSF)
SP Min Ic(77KSF) 32T spec
I c a
t 77
K S
F A
I c a
t 18
o 4
2K
ext
rap
ola
ted
to 1
7T
A
Tape
Progress in Ic measurements SP60 ndash SP207 Data arranged by NHMFL numbers ndash delivery time line
Tapes SP65 66 79 80 were sent for developing winding technique
144 lengths 60 m or 110 m each
100 110 120 130 140 150 160 170 1800
10
20
30
40
50
Nu
mb
er
of s
am
ple
s
Ic(SF77K) A
Histogram of Ic measured at 77K SF
ltIcgt=130 A SD=105
150 200 250 300 350 400 450 500 550 6000
5
10
15
20
25
30
35
Nu
mb
er
of s
am
ple
s
Ic(4K18o17T) A
Histogram for Ic measured at 42 K 17 T 18deg
Before we were dealing mostlywith this conductor produced with M3 machine
Now we are receiving more M4 tapes suitable for top and bottom parts of the magnet
M4 16 Ic variability
M3 16 of Ic variability
0 20 40 60 80 100 120 1400
50
100
150
200
250
300
350
400
450
500
550
600
650
700
75010
2910
38 1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-1 1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4 10
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-3 1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4 1062
-410
63-2
1063
-210
63-2 10
67-2
1071
-210
72-3 10
78-2
1078
-2 1078
-210
78-2
1084
-210
88-2
1088
-210
89-2
1094
-210
94-2
1111
-211
11-2
1115
-218
0-3
180-
418
2-2
182-
218
2-4
195-
2 195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2 218-
221
8-2 21
8-2
218-
221
9-2
219-
221
9-2
219-
221
9-2
219-
2 219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
2 246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
7-2
247-
2
ltIc(4K17T18o)gt
Inner Ic(4K17T18o)
Outer Ic(4K17T18o)
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4passed with large margin
M3
Ic(4K17T18o) data arranged as ascending SuperPower run number (we assume it as time line for each M3 M4 machine)
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
=159
=105
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
Additional techniques used for study properties of ReBCO tapes
bull 16 T Quantum design PPMS for measuring in- field
variable temperature angular dependence of Ic and R(T)
bull Rotator with split coil electromagnet 1T 77K for
measuring angular dependence of Ic in full width tapes
bull YateStar system for measuring distribution of transport
critical current at 77K 08T 50 75 100 125 150 175 200 225 250 275 3000
5
10
15
20
25
30
35
40
45
50
55
60
65
70
T=77K B=1 T
SP125 inner SuNAM
I c A
degree
-30 0 30 60 90 120 150 180 210
10
1T 2T 4T 8T 12T 16T
J c M
Ac
m2
degree904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
RR
(30
0K
)
Temperature (K)
Contact resistance of lap joints
Contact resistance arranged by SP process run numberSmall spread within each run but has large difference between some runs
Maximum average160 nW cm2
Peak maximum230 nW cm2
Measurements done on standard lap joints with 80 mm overlap80 mm
32T spec
M3-1033M3-1062have low Ic (4K) and high joint resistance
T=77K SF
0 20 40 60 80 1000
100
200
300
40010
22-1
1024
-310
28-1
1029
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
1038
1038
1038
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4
1048
-210
48-2 10
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-2 1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-2 1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2 11
11-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2 21
7-2
217-
421
8-2 21
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
M3
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
M4
Measurements of in-field critical currents at fixed orientation
Ic(42K18oB)
Typical Ic(B) dependence measured as field rises and decreases and current rises and decreases (LabView screenshot)
No hysteresis and no damage during field sweep
SP62 inner part of length (N5)Bias current measured from 200 A DI=2 AThis field dependence was measured during 39 minDepending on Ic values field dependence takes 34 min ndash 40 min
8 9 10 11 12 13 14 15 16 17
250
300
350
400
450
500
550600650700
UP SP60 inner Down SP60 inner UP SP60 out Down SP60 out UP SP61 out Down SP61 out UP SP61 inner Down SP61 inner UP SP62 inner Down SP62 inner UP SP62 out Down SP62 out UP SP63 out Down SP63 out
I c A
B T
Representative selection of Ic(B) curves measured at 42 K with 18o between sample plane and B
Orange horizontal line represents 256A minimum specified at 17T
B
Most of measured samples have Ic gt 256 A
No hysteresis in increasing and decreasing field These data have tight fit to Ic~B-a
I
60 80 100 120 140 160 180 2000
50
100
150
200
250
300
350
400
450
500
550
600
650
700
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700 outer I
c(4K17T18o)
inner Ic(4K17T18o)
outer Ic(77KSF)
inner Ic(77KSF)
SP Min Ic(77KSF) 32T spec
I c a
t 77
K S
F A
I c a
t 18
o 4
2K
ext
rap
ola
ted
to 1
7T
A
Tape
Progress in Ic measurements SP60 ndash SP207 Data arranged by NHMFL numbers ndash delivery time line
Tapes SP65 66 79 80 were sent for developing winding technique
144 lengths 60 m or 110 m each
100 110 120 130 140 150 160 170 1800
10
20
30
40
50
Nu
mb
er
of s
am
ple
s
Ic(SF77K) A
Histogram of Ic measured at 77K SF
ltIcgt=130 A SD=105
150 200 250 300 350 400 450 500 550 6000
5
10
15
20
25
30
35
Nu
mb
er
of s
am
ple
s
Ic(4K18o17T) A
Histogram for Ic measured at 42 K 17 T 18deg
Before we were dealing mostlywith this conductor produced with M3 machine
Now we are receiving more M4 tapes suitable for top and bottom parts of the magnet
M4 16 Ic variability
M3 16 of Ic variability
0 20 40 60 80 100 120 1400
50
100
150
200
250
300
350
400
450
500
550
600
650
700
75010
2910
38 1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-1 1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4 10
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-3 1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4 1062
-410
63-2
1063
-210
63-2 10
67-2
1071
-210
72-3 10
78-2
1078
-2 1078
-210
78-2
1084
-210
88-2
1088
-210
89-2
1094
-210
94-2
1111
-211
11-2
1115
-218
0-3
180-
418
2-2
182-
218
2-4
195-
2 195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2 218-
221
8-2 21
8-2
218-
221
9-2
219-
221
9-2
219-
221
9-2
219-
2 219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
2 246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
7-2
247-
2
ltIc(4K17T18o)gt
Inner Ic(4K17T18o)
Outer Ic(4K17T18o)
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4passed with large margin
M3
Ic(4K17T18o) data arranged as ascending SuperPower run number (we assume it as time line for each M3 M4 machine)
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
=159
=105
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
Contact resistance of lap joints
Contact resistance arranged by SP process run numberSmall spread within each run but has large difference between some runs
Maximum average160 nW cm2
Peak maximum230 nW cm2
Measurements done on standard lap joints with 80 mm overlap80 mm
32T spec
M3-1033M3-1062have low Ic (4K) and high joint resistance
T=77K SF
0 20 40 60 80 1000
100
200
300
40010
22-1
1024
-310
28-1
1029
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
1038
1038
1038
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4
1048
-210
48-2 10
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-2 1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-2 1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2 11
11-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2 21
7-2
217-
421
8-2 21
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
M3
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
M4
Measurements of in-field critical currents at fixed orientation
Ic(42K18oB)
Typical Ic(B) dependence measured as field rises and decreases and current rises and decreases (LabView screenshot)
No hysteresis and no damage during field sweep
SP62 inner part of length (N5)Bias current measured from 200 A DI=2 AThis field dependence was measured during 39 minDepending on Ic values field dependence takes 34 min ndash 40 min
8 9 10 11 12 13 14 15 16 17
250
300
350
400
450
500
550600650700
UP SP60 inner Down SP60 inner UP SP60 out Down SP60 out UP SP61 out Down SP61 out UP SP61 inner Down SP61 inner UP SP62 inner Down SP62 inner UP SP62 out Down SP62 out UP SP63 out Down SP63 out
I c A
B T
Representative selection of Ic(B) curves measured at 42 K with 18o between sample plane and B
Orange horizontal line represents 256A minimum specified at 17T
B
Most of measured samples have Ic gt 256 A
No hysteresis in increasing and decreasing field These data have tight fit to Ic~B-a
I
60 80 100 120 140 160 180 2000
50
100
150
200
250
300
350
400
450
500
550
600
650
700
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700 outer I
c(4K17T18o)
inner Ic(4K17T18o)
outer Ic(77KSF)
inner Ic(77KSF)
SP Min Ic(77KSF) 32T spec
I c a
t 77
K S
F A
I c a
t 18
o 4
2K
ext
rap
ola
ted
to 1
7T
A
Tape
Progress in Ic measurements SP60 ndash SP207 Data arranged by NHMFL numbers ndash delivery time line
Tapes SP65 66 79 80 were sent for developing winding technique
144 lengths 60 m or 110 m each
100 110 120 130 140 150 160 170 1800
10
20
30
40
50
Nu
mb
er
of s
am
ple
s
Ic(SF77K) A
Histogram of Ic measured at 77K SF
ltIcgt=130 A SD=105
150 200 250 300 350 400 450 500 550 6000
5
10
15
20
25
30
35
Nu
mb
er
of s
am
ple
s
Ic(4K18o17T) A
Histogram for Ic measured at 42 K 17 T 18deg
Before we were dealing mostlywith this conductor produced with M3 machine
Now we are receiving more M4 tapes suitable for top and bottom parts of the magnet
M4 16 Ic variability
M3 16 of Ic variability
0 20 40 60 80 100 120 1400
50
100
150
200
250
300
350
400
450
500
550
600
650
700
75010
2910
38 1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-1 1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4 10
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-3 1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4 1062
-410
63-2
1063
-210
63-2 10
67-2
1071
-210
72-3 10
78-2
1078
-2 1078
-210
78-2
1084
-210
88-2
1088
-210
89-2
1094
-210
94-2
1111
-211
11-2
1115
-218
0-3
180-
418
2-2
182-
218
2-4
195-
2 195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2 218-
221
8-2 21
8-2
218-
221
9-2
219-
221
9-2
219-
221
9-2
219-
2 219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
2 246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
7-2
247-
2
ltIc(4K17T18o)gt
Inner Ic(4K17T18o)
Outer Ic(4K17T18o)
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4passed with large margin
M3
Ic(4K17T18o) data arranged as ascending SuperPower run number (we assume it as time line for each M3 M4 machine)
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
=159
=105
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
Contact resistance arranged by SP process run numberSmall spread within each run but has large difference between some runs
Maximum average160 nW cm2
Peak maximum230 nW cm2
Measurements done on standard lap joints with 80 mm overlap80 mm
32T spec
M3-1033M3-1062have low Ic (4K) and high joint resistance
T=77K SF
0 20 40 60 80 1000
100
200
300
40010
22-1
1024
-310
28-1
1029
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
1038
1038
1038
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4
1048
-210
48-2 10
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-2 1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-2 1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2 11
11-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2 21
7-2
217-
421
8-2 21
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
M3
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
M4
Measurements of in-field critical currents at fixed orientation
Ic(42K18oB)
Typical Ic(B) dependence measured as field rises and decreases and current rises and decreases (LabView screenshot)
No hysteresis and no damage during field sweep
SP62 inner part of length (N5)Bias current measured from 200 A DI=2 AThis field dependence was measured during 39 minDepending on Ic values field dependence takes 34 min ndash 40 min
8 9 10 11 12 13 14 15 16 17
250
300
350
400
450
500
550600650700
UP SP60 inner Down SP60 inner UP SP60 out Down SP60 out UP SP61 out Down SP61 out UP SP61 inner Down SP61 inner UP SP62 inner Down SP62 inner UP SP62 out Down SP62 out UP SP63 out Down SP63 out
I c A
B T
Representative selection of Ic(B) curves measured at 42 K with 18o between sample plane and B
Orange horizontal line represents 256A minimum specified at 17T
B
Most of measured samples have Ic gt 256 A
No hysteresis in increasing and decreasing field These data have tight fit to Ic~B-a
I
60 80 100 120 140 160 180 2000
50
100
150
200
250
300
350
400
450
500
550
600
650
700
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700 outer I
c(4K17T18o)
inner Ic(4K17T18o)
outer Ic(77KSF)
inner Ic(77KSF)
SP Min Ic(77KSF) 32T spec
I c a
t 77
K S
F A
I c a
t 18
o 4
2K
ext
rap
ola
ted
to 1
7T
A
Tape
Progress in Ic measurements SP60 ndash SP207 Data arranged by NHMFL numbers ndash delivery time line
Tapes SP65 66 79 80 were sent for developing winding technique
144 lengths 60 m or 110 m each
100 110 120 130 140 150 160 170 1800
10
20
30
40
50
Nu
mb
er
of s
am
ple
s
Ic(SF77K) A
Histogram of Ic measured at 77K SF
ltIcgt=130 A SD=105
150 200 250 300 350 400 450 500 550 6000
5
10
15
20
25
30
35
Nu
mb
er
of s
am
ple
s
Ic(4K18o17T) A
Histogram for Ic measured at 42 K 17 T 18deg
Before we were dealing mostlywith this conductor produced with M3 machine
Now we are receiving more M4 tapes suitable for top and bottom parts of the magnet
M4 16 Ic variability
M3 16 of Ic variability
0 20 40 60 80 100 120 1400
50
100
150
200
250
300
350
400
450
500
550
600
650
700
75010
2910
38 1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-1 1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4 10
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-3 1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4 1062
-410
63-2
1063
-210
63-2 10
67-2
1071
-210
72-3 10
78-2
1078
-2 1078
-210
78-2
1084
-210
88-2
1088
-210
89-2
1094
-210
94-2
1111
-211
11-2
1115
-218
0-3
180-
418
2-2
182-
218
2-4
195-
2 195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2 218-
221
8-2 21
8-2
218-
221
9-2
219-
221
9-2
219-
221
9-2
219-
2 219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
2 246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
7-2
247-
2
ltIc(4K17T18o)gt
Inner Ic(4K17T18o)
Outer Ic(4K17T18o)
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4passed with large margin
M3
Ic(4K17T18o) data arranged as ascending SuperPower run number (we assume it as time line for each M3 M4 machine)
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
=159
=105
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
Measurements of in-field critical currents at fixed orientation
Ic(42K18oB)
Typical Ic(B) dependence measured as field rises and decreases and current rises and decreases (LabView screenshot)
No hysteresis and no damage during field sweep
SP62 inner part of length (N5)Bias current measured from 200 A DI=2 AThis field dependence was measured during 39 minDepending on Ic values field dependence takes 34 min ndash 40 min
8 9 10 11 12 13 14 15 16 17
250
300
350
400
450
500
550600650700
UP SP60 inner Down SP60 inner UP SP60 out Down SP60 out UP SP61 out Down SP61 out UP SP61 inner Down SP61 inner UP SP62 inner Down SP62 inner UP SP62 out Down SP62 out UP SP63 out Down SP63 out
I c A
B T
Representative selection of Ic(B) curves measured at 42 K with 18o between sample plane and B
Orange horizontal line represents 256A minimum specified at 17T
B
Most of measured samples have Ic gt 256 A
No hysteresis in increasing and decreasing field These data have tight fit to Ic~B-a
I
60 80 100 120 140 160 180 2000
50
100
150
200
250
300
350
400
450
500
550
600
650
700
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700 outer I
c(4K17T18o)
inner Ic(4K17T18o)
outer Ic(77KSF)
inner Ic(77KSF)
SP Min Ic(77KSF) 32T spec
I c a
t 77
K S
F A
I c a
t 18
o 4
2K
ext
rap
ola
ted
to 1
7T
A
Tape
Progress in Ic measurements SP60 ndash SP207 Data arranged by NHMFL numbers ndash delivery time line
Tapes SP65 66 79 80 were sent for developing winding technique
144 lengths 60 m or 110 m each
100 110 120 130 140 150 160 170 1800
10
20
30
40
50
Nu
mb
er
of s
am
ple
s
Ic(SF77K) A
Histogram of Ic measured at 77K SF
ltIcgt=130 A SD=105
150 200 250 300 350 400 450 500 550 6000
5
10
15
20
25
30
35
Nu
mb
er
of s
am
ple
s
Ic(4K18o17T) A
Histogram for Ic measured at 42 K 17 T 18deg
Before we were dealing mostlywith this conductor produced with M3 machine
Now we are receiving more M4 tapes suitable for top and bottom parts of the magnet
M4 16 Ic variability
M3 16 of Ic variability
0 20 40 60 80 100 120 1400
50
100
150
200
250
300
350
400
450
500
550
600
650
700
75010
2910
38 1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-1 1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4 10
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-3 1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4 1062
-410
63-2
1063
-210
63-2 10
67-2
1071
-210
72-3 10
78-2
1078
-2 1078
-210
78-2
1084
-210
88-2
1088
-210
89-2
1094
-210
94-2
1111
-211
11-2
1115
-218
0-3
180-
418
2-2
182-
218
2-4
195-
2 195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2 218-
221
8-2 21
8-2
218-
221
9-2
219-
221
9-2
219-
221
9-2
219-
2 219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
2 246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
7-2
247-
2
ltIc(4K17T18o)gt
Inner Ic(4K17T18o)
Outer Ic(4K17T18o)
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4passed with large margin
M3
Ic(4K17T18o) data arranged as ascending SuperPower run number (we assume it as time line for each M3 M4 machine)
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
=159
=105
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
Typical Ic(B) dependence measured as field rises and decreases and current rises and decreases (LabView screenshot)
No hysteresis and no damage during field sweep
SP62 inner part of length (N5)Bias current measured from 200 A DI=2 AThis field dependence was measured during 39 minDepending on Ic values field dependence takes 34 min ndash 40 min
8 9 10 11 12 13 14 15 16 17
250
300
350
400
450
500
550600650700
UP SP60 inner Down SP60 inner UP SP60 out Down SP60 out UP SP61 out Down SP61 out UP SP61 inner Down SP61 inner UP SP62 inner Down SP62 inner UP SP62 out Down SP62 out UP SP63 out Down SP63 out
I c A
B T
Representative selection of Ic(B) curves measured at 42 K with 18o between sample plane and B
Orange horizontal line represents 256A minimum specified at 17T
B
Most of measured samples have Ic gt 256 A
No hysteresis in increasing and decreasing field These data have tight fit to Ic~B-a
I
60 80 100 120 140 160 180 2000
50
100
150
200
250
300
350
400
450
500
550
600
650
700
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700 outer I
c(4K17T18o)
inner Ic(4K17T18o)
outer Ic(77KSF)
inner Ic(77KSF)
SP Min Ic(77KSF) 32T spec
I c a
t 77
K S
F A
I c a
t 18
o 4
2K
ext
rap
ola
ted
to 1
7T
A
Tape
Progress in Ic measurements SP60 ndash SP207 Data arranged by NHMFL numbers ndash delivery time line
Tapes SP65 66 79 80 were sent for developing winding technique
144 lengths 60 m or 110 m each
100 110 120 130 140 150 160 170 1800
10
20
30
40
50
Nu
mb
er
of s
am
ple
s
Ic(SF77K) A
Histogram of Ic measured at 77K SF
ltIcgt=130 A SD=105
150 200 250 300 350 400 450 500 550 6000
5
10
15
20
25
30
35
Nu
mb
er
of s
am
ple
s
Ic(4K18o17T) A
Histogram for Ic measured at 42 K 17 T 18deg
Before we were dealing mostlywith this conductor produced with M3 machine
Now we are receiving more M4 tapes suitable for top and bottom parts of the magnet
M4 16 Ic variability
M3 16 of Ic variability
0 20 40 60 80 100 120 1400
50
100
150
200
250
300
350
400
450
500
550
600
650
700
75010
2910
38 1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-1 1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4 10
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-3 1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4 1062
-410
63-2
1063
-210
63-2 10
67-2
1071
-210
72-3 10
78-2
1078
-2 1078
-210
78-2
1084
-210
88-2
1088
-210
89-2
1094
-210
94-2
1111
-211
11-2
1115
-218
0-3
180-
418
2-2
182-
218
2-4
195-
2 195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2 218-
221
8-2 21
8-2
218-
221
9-2
219-
221
9-2
219-
221
9-2
219-
2 219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
2 246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
7-2
247-
2
ltIc(4K17T18o)gt
Inner Ic(4K17T18o)
Outer Ic(4K17T18o)
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4passed with large margin
M3
Ic(4K17T18o) data arranged as ascending SuperPower run number (we assume it as time line for each M3 M4 machine)
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
=159
=105
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
8 9 10 11 12 13 14 15 16 17
250
300
350
400
450
500
550600650700
UP SP60 inner Down SP60 inner UP SP60 out Down SP60 out UP SP61 out Down SP61 out UP SP61 inner Down SP61 inner UP SP62 inner Down SP62 inner UP SP62 out Down SP62 out UP SP63 out Down SP63 out
I c A
B T
Representative selection of Ic(B) curves measured at 42 K with 18o between sample plane and B
Orange horizontal line represents 256A minimum specified at 17T
B
Most of measured samples have Ic gt 256 A
No hysteresis in increasing and decreasing field These data have tight fit to Ic~B-a
I
60 80 100 120 140 160 180 2000
50
100
150
200
250
300
350
400
450
500
550
600
650
700
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700 outer I
c(4K17T18o)
inner Ic(4K17T18o)
outer Ic(77KSF)
inner Ic(77KSF)
SP Min Ic(77KSF) 32T spec
I c a
t 77
K S
F A
I c a
t 18
o 4
2K
ext
rap
ola
ted
to 1
7T
A
Tape
Progress in Ic measurements SP60 ndash SP207 Data arranged by NHMFL numbers ndash delivery time line
Tapes SP65 66 79 80 were sent for developing winding technique
144 lengths 60 m or 110 m each
100 110 120 130 140 150 160 170 1800
10
20
30
40
50
Nu
mb
er
of s
am
ple
s
Ic(SF77K) A
Histogram of Ic measured at 77K SF
ltIcgt=130 A SD=105
150 200 250 300 350 400 450 500 550 6000
5
10
15
20
25
30
35
Nu
mb
er
of s
am
ple
s
Ic(4K18o17T) A
Histogram for Ic measured at 42 K 17 T 18deg
Before we were dealing mostlywith this conductor produced with M3 machine
Now we are receiving more M4 tapes suitable for top and bottom parts of the magnet
M4 16 Ic variability
M3 16 of Ic variability
0 20 40 60 80 100 120 1400
50
100
150
200
250
300
350
400
450
500
550
600
650
700
75010
2910
38 1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-1 1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4 10
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-3 1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4 1062
-410
63-2
1063
-210
63-2 10
67-2
1071
-210
72-3 10
78-2
1078
-2 1078
-210
78-2
1084
-210
88-2
1088
-210
89-2
1094
-210
94-2
1111
-211
11-2
1115
-218
0-3
180-
418
2-2
182-
218
2-4
195-
2 195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2 218-
221
8-2 21
8-2
218-
221
9-2
219-
221
9-2
219-
221
9-2
219-
2 219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
2 246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
7-2
247-
2
ltIc(4K17T18o)gt
Inner Ic(4K17T18o)
Outer Ic(4K17T18o)
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4passed with large margin
M3
Ic(4K17T18o) data arranged as ascending SuperPower run number (we assume it as time line for each M3 M4 machine)
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
=159
=105
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
60 80 100 120 140 160 180 2000
50
100
150
200
250
300
350
400
450
500
550
600
650
700
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700 outer I
c(4K17T18o)
inner Ic(4K17T18o)
outer Ic(77KSF)
inner Ic(77KSF)
SP Min Ic(77KSF) 32T spec
I c a
t 77
K S
F A
I c a
t 18
o 4
2K
ext
rap
ola
ted
to 1
7T
A
Tape
Progress in Ic measurements SP60 ndash SP207 Data arranged by NHMFL numbers ndash delivery time line
Tapes SP65 66 79 80 were sent for developing winding technique
144 lengths 60 m or 110 m each
100 110 120 130 140 150 160 170 1800
10
20
30
40
50
Nu
mb
er
of s
am
ple
s
Ic(SF77K) A
Histogram of Ic measured at 77K SF
ltIcgt=130 A SD=105
150 200 250 300 350 400 450 500 550 6000
5
10
15
20
25
30
35
Nu
mb
er
of s
am
ple
s
Ic(4K18o17T) A
Histogram for Ic measured at 42 K 17 T 18deg
Before we were dealing mostlywith this conductor produced with M3 machine
Now we are receiving more M4 tapes suitable for top and bottom parts of the magnet
M4 16 Ic variability
M3 16 of Ic variability
0 20 40 60 80 100 120 1400
50
100
150
200
250
300
350
400
450
500
550
600
650
700
75010
2910
38 1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-1 1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4 10
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-3 1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4 1062
-410
63-2
1063
-210
63-2 10
67-2
1071
-210
72-3 10
78-2
1078
-2 1078
-210
78-2
1084
-210
88-2
1088
-210
89-2
1094
-210
94-2
1111
-211
11-2
1115
-218
0-3
180-
418
2-2
182-
218
2-4
195-
2 195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2 218-
221
8-2 21
8-2
218-
221
9-2
219-
221
9-2
219-
221
9-2
219-
2 219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
2 246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
7-2
247-
2
ltIc(4K17T18o)gt
Inner Ic(4K17T18o)
Outer Ic(4K17T18o)
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4passed with large margin
M3
Ic(4K17T18o) data arranged as ascending SuperPower run number (we assume it as time line for each M3 M4 machine)
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
=159
=105
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
100 110 120 130 140 150 160 170 1800
10
20
30
40
50
Nu
mb
er
of s
am
ple
s
Ic(SF77K) A
Histogram of Ic measured at 77K SF
ltIcgt=130 A SD=105
150 200 250 300 350 400 450 500 550 6000
5
10
15
20
25
30
35
Nu
mb
er
of s
am
ple
s
Ic(4K18o17T) A
Histogram for Ic measured at 42 K 17 T 18deg
Before we were dealing mostlywith this conductor produced with M3 machine
Now we are receiving more M4 tapes suitable for top and bottom parts of the magnet
M4 16 Ic variability
M3 16 of Ic variability
0 20 40 60 80 100 120 1400
50
100
150
200
250
300
350
400
450
500
550
600
650
700
75010
2910
38 1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-1 1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4 10
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-3 1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4 1062
-410
63-2
1063
-210
63-2 10
67-2
1071
-210
72-3 10
78-2
1078
-2 1078
-210
78-2
1084
-210
88-2
1088
-210
89-2
1094
-210
94-2
1111
-211
11-2
1115
-218
0-3
180-
418
2-2
182-
218
2-4
195-
2 195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2 218-
221
8-2 21
8-2
218-
221
9-2
219-
221
9-2
219-
221
9-2
219-
2 219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
2 246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
7-2
247-
2
ltIc(4K17T18o)gt
Inner Ic(4K17T18o)
Outer Ic(4K17T18o)
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4passed with large margin
M3
Ic(4K17T18o) data arranged as ascending SuperPower run number (we assume it as time line for each M3 M4 machine)
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
=159
=105
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
150 200 250 300 350 400 450 500 550 6000
5
10
15
20
25
30
35
Nu
mb
er
of s
am
ple
s
Ic(4K18o17T) A
Histogram for Ic measured at 42 K 17 T 18deg
Before we were dealing mostlywith this conductor produced with M3 machine
Now we are receiving more M4 tapes suitable for top and bottom parts of the magnet
M4 16 Ic variability
M3 16 of Ic variability
0 20 40 60 80 100 120 1400
50
100
150
200
250
300
350
400
450
500
550
600
650
700
75010
2910
38 1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-1 1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4 10
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-3 1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4 1062
-410
63-2
1063
-210
63-2 10
67-2
1071
-210
72-3 10
78-2
1078
-2 1078
-210
78-2
1084
-210
88-2
1088
-210
89-2
1094
-210
94-2
1111
-211
11-2
1115
-218
0-3
180-
418
2-2
182-
218
2-4
195-
2 195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2 218-
221
8-2 21
8-2
218-
221
9-2
219-
221
9-2
219-
221
9-2
219-
2 219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
2 246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
7-2
247-
2
ltIc(4K17T18o)gt
Inner Ic(4K17T18o)
Outer Ic(4K17T18o)
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4passed with large margin
M3
Ic(4K17T18o) data arranged as ascending SuperPower run number (we assume it as time line for each M3 M4 machine)
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
=159
=105
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
0 20 40 60 80 100 120 1400
50
100
150
200
250
300
350
400
450
500
550
600
650
700
75010
2910
38 1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-1 1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1043
-210
45-3
1045
-310
45-3
1045
-310
47-4 10
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-3 1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4 1062
-410
63-2
1063
-210
63-2 10
67-2
1071
-210
72-3 10
78-2
1078
-2 1078
-210
78-2
1084
-210
88-2
1088
-210
89-2
1094
-210
94-2
1111
-211
11-2
1115
-218
0-3
180-
418
2-2
182-
218
2-4
195-
2 195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2 218-
221
8-2 21
8-2
218-
221
9-2
219-
221
9-2
219-
221
9-2
219-
2 219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
2 246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
7-2
247-
2
ltIc(4K17T18o)gt
Inner Ic(4K17T18o)
Outer Ic(4K17T18o)
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4passed with large margin
M3
Ic(4K17T18o) data arranged as ascending SuperPower run number (we assume it as time line for each M3 M4 machine)
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
=159
=105
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
=159
=105
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
=159
=105
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
0 20 40 60 80 100 120 140 160 1800
50
100
150
200
250
300
350
400
450
500
550
600
650
M3 inner M3 outer M4 inner M4 outer
I c a
t 42
K e
xtra
po
late
d to
17
T A
Ic SF 77K A
We are getting two types of conductors from different SuperPower Inc machines with averaged lift factors 221 (M3) and 336 (M4)
=159
=105
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
200 300 400 500 600 70000
01
02
03
04
05
06
07
08
09
10
M3 inner M3 outer M4 inner M4 outer
Ic at 42K extrapolated to 17T A
M3 ltIcgt =283 A lt gt=a 083 +- 004
M4 ltIcgt =450 A lt gt=a 084 +- 005
No dramatic changes in a values Interpretation pinning mechanism is probably similar for low Ic and high Ic tapes
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
0 20 40 60 80 100 120
-25
-20
-15
-10
-5
0
5
10
15
20
2510
2910
3810
3810
3810
3810
22-1
1024
-310
28-1
1029
-110
30-1
1030
-110
30-1
1031
-210
31-2
1033
-210
33-2
1033
-210
33-2
1038
-2 1038
-210
38-2 10
38-2
1038
-210
38-2
1038
-2 1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2
1048
-210
50-4
1052
-310
52-3
1052
-310
52-3
1060
-210
60-3
1061
-210
61-2
1061
-2 1061
-210
61-2
1061
-210
61-2
1061
-210
61-2
1062
-210
62-4
1062
-410
63-2
1063
-210
63-2
1067
-210
71-2
1072
-310
78-2
1078
-210
78-2
1078
-210
84-2
1088
-210
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
4 195-
219
5-2
217-
221
7-2
217-
221
7-2
217-
421
8-2
218-
221
8-2
218-
2 218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
Standard deviation 57
At 77K SF just few tapes have relative spread above 10End to end relative variation of Ic(77K SF)
100
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
0 20 40 60 80 100 120-50
-40
-30
-20
-10
0
10
20
30
40
50
1029
1038
1038
1038
1038
1022
-110
24-3
1028
-110
29-1
1030
-110
30-1
1030
-110
31-2
1031
-210
33-2
1033
-210
33-2
1033
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
38-2
1038
-210
43-2
1045
-310
45-3
1045
-310
45-3
1047
-410
48-2
1048
-210
48-2
1048
-210
48-2 10
48-2
1050
-410
52-3
1052
-310
52-3
1052
-310
60-2
1060
-310
61-2
1061
-210
61-2
1061
-210
61-2
1061
-210
61-2 10
61-2
1061
-210
62-2
1062
-410
62-4
1063
-210
63-2
1063
-210
67-2
1071
-210
72-3
1078
-210
78-2 10
78-2
1078
-210
84-2 10
88-2 10
88-2
1089
-210
94-2
1094
-211
11-2
1111
-211
15-2
180-
318
0-4
182-
218
2-2
182-
419
5-2
195-
221
7-2
217-
221
7-2
217-
221
7-4
218-
221
8-2
218-
221
8-2
218-
221
8-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
219-
221
9-2
236-
223
9-3
239-
323
9-3
245-
3
245-
324
5-3
245-
324
5-3
245-
324
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
246-
224
6-2
247-
224
7-2
Tape
At 42K in-field more tapes have relative spread above 1010
0End to end relative variation of Ic(4K 17T 18o)
Standard deviation 96
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
Same Ic(4K17T18o) data as on previous slide but arranged as ascending lt Ic(4K17T18o) gt Observations small difference in Ic for samples from different ends
Tapes within one process have similar Ic M4 process yields tapes with higher Ic Uniform distribution with two steps at 270A and 480A
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
SP64 innerSP60 inner
SEM images of ReBCO surface Larger and irregularly shaped grains on SP60 more needle like grains for SP62-64 staircase like surface for SP60 but flat surface for SP61-64
After etching Cu and Ag
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
Ag
ReBCO
SEM cross-section of M4 SP129
SEM cross-section of M3 SP159
Ag
ReBCO
Different thickness for M3 and M4 machines
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
0 20 40 60 80 100 120150
200
250
300
350
400
450
500
550
600
650
700
121 0
92
095
5
096
1 108 107
155 152 1
5 153 1
53 15
146
5 155
16
156
ltIc(4 K 17 T 18 deg)gt
Ic(4 K 17 T 18 deg) inner
Ic(4 K 17 T 18 deg) outer
32T spec
I c(4K
17
T 1
8o)
A
Tape
M4
M3
Ascending lt Ic(4K17T18o) gt plot with ReBCO thicknesses
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
08 10 12 14 1600
05
10
15
20
25
30
35
40
45
50
55
1029
103810
24-3
1030
-1
1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-221
9-2
236-
223
9-3
239-
3
J c at 7
7K
SF
MA
cm
2
ReBCO thickness m
77K self-field critical current vs ReBCO thickness dependence
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
08 10 12 14 160
2
4
6
8
10
1029
1038
1024
-3
1030
-1 1030
-1
1060
-2
1084
-2
217-
2
217-
2
218-
221
9-2
219-
2
236-
223
9-3
239-
3
J c at 4
2K
ext
rap
ola
ted
to 1
7T
MA
cm
2
ReBCO thickness m
M3
M4
4K in-field critical current density vs ReBCO thickness dependence
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
Testing geometrical tolerances
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
0 1 2 3 4
120
130
140
150
160
170
180
SP60 inner SP60 outer SP61 inner SP61 outer SP62 inner SP62 outer SP63 inner SP63 outer SP64 inner SP64 outer
Th
ickn
ess
m
Width mm
Thickness profiles measured with Nikon microscope
All profiles are nearly the same
Optical image of typical cross section (SP 60 inner)
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
Width distributions for SP60 ndash SP64 tapes are within specification
0 100 200 300 400 500 600404
406
408
410
412
414
416
SP60 inner SP61 inner SP62 inner SP63 inner SP64 inner SP60 outer SP61 Outer SP62 Outer SP63 Outer SP64 Outer Max Min
W
m
m
L mm
We noticed considerable improvement of tape width uniformity which eliminates substantial part
of variations in Ic and mechanical properties
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
120 125 130 135 140 145 150 155 160 165 170 175
406
408
410
412
414
416
418
420
422
424
426
428
430
max min mean 32T spec Min 32T spec Max
Wid
th
mm
SP number
Conductor width variation
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
120 125 130 135 140 145 150 155 160 165 170 175140
145
150
155
160
165
170
175
180
To
tal t
hic
kne
ss
um
SP number
Total thickness measured with micrometer
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
120 125 130 135 140 145 150 155 160 165 170 175037
038
039
040
041
042
043
044
045
Cu
are
a
mm
2
SP number
Cu area for SP125- 166 tapes
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
0 10 20 30 40 50 60 70 80 90 100 110 1200
10
20
30
40
50
60
70
80
90
1024
-3
1030
-110
30-1 10
33-2
1033
-210
38-2
1038
-2
1045
-3
1048
-2
1052
-310
52-3
1052
-3
1062
-410
62-4
1063
-210
63-2
1078
-2
180-
318
0-4
182-
419
5-2
217-
2 218-
221
8-2
218-
221
8-2
218-
221
9-2
219-
221
9-2
219-
2
219-
2
Co
nta
ct r
esi
sta
nce
n
cm2
Tape
RRR of stabilizer ndash parallel connection of Ag and Cu layers
RRR meets the specification
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
Comparison of 4K in- field Ic for conductors from different
manufacturers
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
1 10
100
200
300
400
500
600700
SuNAM N1 SuNAM N2 SuperOx N2 SuperOx N3 SuperOx N4 AMSC Fujikura N1 Fujikura N2 SP77 SP129 N1 SP129 N2 SP132 N1 SP132 N2 SP127
I c A
B T
Comparison Ic(4K B) for tapes from different manufacturers measured up to 312TOrientation field perpendicular to tape plane
B
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
1 10100
1000
SP67 innerB at 18deg
SP83 innerB at 18deg
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
1400A
700 A
SP64 inner
SP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
1050 A
FujikuraB at 18deg
GdBCO
SP89outerB at 18deg
Comparison of Ic(4KB) in ReBCO conductors in-field up to 135T
T=4KIc(B) measured in OX IIMax field is 135T
Close to SP average
SP Min Ic
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
GdBCO FujikuraBIIc
SP108 out
Bi_130222_pmm120822_143_A70OP round wire diameter 1386mm
1400A
700 A
Bi_130222_pmm120822_143_A71OP round wire diameter 1399mm
Bi-2212 round wire
SP64 innerSP63 inner
ReBCOSP 2013 (2x50um thick Cu) BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
I c A
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108in
Bi-2212 round wire130222pmm12082210A6610mm
OP130508-27x7-7-100bar-B48diameter 06883 mm ff=10
1050 A
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
FujikuraB at 18deg
GdBCO
Comparison of conductor performances at 42K up to 135TMeasured in OX II using up to 4 Sorensen DSC8-350E
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
Manufacturer Material a at BIIc a at 18deg
SuperPower ReBCO 067-076 07-09
SuNAM ReBCO 06 06 069 068
SuperOx ReBCO 054 054 0588 059
Fujikura ReBCO 0641 069 070
AMSC ReBCO 074
Sumitomo Bi-2223 018 0164
OP processed Bi-2212- round d=138mm 033
OP processed Bi-2212 d=1154 mm 027 026 0238
OP processed Bi-2212 d=0688 mm 027
Comparison of a values
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
1 10100
1000
ReBCO
SuperOx B at 18o
ReBCOSuperOx BIIc
SP108in
Bi_2212130222_pmm120822_143_A70OP round wire diameter 1386mm
Bi 2212 130222_pmm 120822_12_A691154 mm round wire
Bi-2212 round wire130222pmm12082210A66
SP64 innerSP63 inner
ReBCOSP 2013(2x50um thick Cu)BII c
Bi-2223Sumitomo 2011 tape BIIc
SP108out
ReBCO2013 SuNAM tapein brass stabilizerB at 18deg to tape
J e
Am
m2
B T
Bi-2223Sumitomo 2012 tape BIIc
ReBCOSP 2013(2x50um thick Cu)B at 18 deg
ReBCO2013 SuNAM tapein brass stabilizerBIIc
SP108 out
Bi2212130222pmm120822_143_A71OP round wire 1399mm
17T
GdBCO
FujikuraB at 18deg
FujikuraBIIc
GdBCO
Comparison of conductor performances at 42KMeasured in OX II using up to 4 Sorensen DSC8-350E
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
0 100 200 300 400 500 600 7000
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
I c(4K
B a
t 18
o)
A
Ic(4K BIIc) A
SuNAM
Fujikura
SuperOxSuperPower
X2
X15
X1
Difference in anisotropy
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
bull Comprehensive analysis of various tape properties is necessary for building reliable magnet
bull Ic measured in specific field orientation at 42K is important for predicting coil performance not testing at self-field 77 K
bull Jc(B 4K 18o) did not dropped as ReBCO thickness got 60 increase in M4 tapes
bull Transport and geometrical properties of commercially available (Re)BCO conductor from SuperPower Inc are not perfect but sufficient for making 32 T user magnet
bull Among ReBCO conductors SuperPower Inc and Fujikura have largest Ic(4K B)
bull Tapes from SuperOx show smallest among ReBCO CC a and smallest Ic anisotropy
Conclusions
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
How to choose operating current after measuring Ic in about 003 - 0018 of the conductor at 4K in-field
Assume that the distribution shown in experimental histogram is ldquouniversalrdquo through every tape from the set SP60-SP124
Here is simple statistical model Ic(x) generated with Gaussian distribution in 6000 point min Ic taken for 10000 virtual tapes
Based on standard deviation of Ic relative difference 935
Assume that minimum size of Ic non-uniformity is about 1 cm for 60m long tape
-50 -45 -40 -35 -300
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
Cou
nt
Min relative Ic change (below average per tape)
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
60 62 64 66 68 70 72 74 76 780
20
40
60
80
100
120
140
160
180
200
220
0
20
40
60
80
100
120
140
160
180
200
220
Inner Ic(4K17TBIIc)
Outer Ic(4K17T BIIc)
Inner Ic(77K SF)
Outer Ic(77K SF)
I c S
F 7
7 K
A
I c ext
rap
ola
ted
to
17
T
42
K
A
Tape Number
B
I
Ic(4K 17T BIIc) with Ic(77K SF) for selected tapes
Anti-correlation
All tapes from M3 machine
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
120 140 160 180 200060
062
064
066
068
070
072
074
076
078
080
082
084
086
60
61
62
6364
6061
6263 64
67
68 69
70
717273
67
68
69
70
7172
73
7475
76
77
78
Ic extrapolated to 17 T 42 K A
Relation between a values and Ic (4K 17T BIIc) For tapes with higher Ic we observe larger a values
Ic~B-a
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
58 60 62 64 66 68 70 72 7400
02
04
06
08
10
12
14
16
18
20
22
Inner Outer
I c(4K
17
T1
8o)
I c(4K
17
T B
IIc)
SP number
Mean 182Standard deviation 012 (66)
Ratio Ic(4K 17T 18o) Ic(4K 17T BIIc) has low spread from tape to tapeInterpretation Angular dependence of Ic has small variation
BIIc and 18o orientations measured on different samples
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
100 150 200 250 300
00
02
04
06
08
10
SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
Normalized R vs T for samples from ldquoinnerrdquo part of spools
MeasurementsTemperature range 300K ndash 89K SFTransport measurements were done with PPMS3-2 samples were measured simultaneously on one packExcitation current 10 mA DT near transition 0025K
Aim By calculating Tc from electric resistivity measurementsfind why Ic at SF 77K for SP60 differs from one for SP61-64
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
904 906 908 910 912 914 916 918 920
000
005
010
015
020
025
030 SP60 inner 1 SP60 inner 2 SP60 inner 3 SP60 inner 4 SP61 inner SP62 inner SP63 inner SP64 inner
R
R(3
00
K)
Temperature (K)
For inner region
Very narrow Tc spread and sharp transition for SP61-64 Samples from SP60 have wider and variable transition regionSome SP60 samples have up to 3 ldquokneerdquo
R vs T for samples from ldquoinnerrdquo part of spools
ldquoinnerrdquo means that sample was cut from inner part of spool arrived from SP
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping
59 60 61 62 63 64 65
906
908
910
912
914
916
918 max dRdT middle dRdT small dRdT
Tp
K
Tape number
bulk critical temperature Tc defined as maximum of dRdT
Striking difference between SP60 and SP61-64SP60 contains several phases with different Tc ranging from 907K to 918K
Peaks of dRdT
Interpretation
SP60 has non-uniform composition with multiple (Re)BCO phases
SP 61-64 have variable through length oxygen doping