Ap

pli

ed S

up

erco

nd

uct

ivit

y R

esea

rch

-

Un

iver

sity

of

Cam

bri

dge

B.A.Glowacki

Fault Current Limiter

Ap

pli

ed S

up

erco

nd

uct

ivit

y R

esea

rch

-

Un

iver

sity

of

Cam

bri

dge

B.A.Glowacki

YBa2Cu3O7 Thin Film Fault current limiter

Qui ckTi me™ and aDV - PAL decompressor

are needed to see thi s pi cture.

Ap

pli

ed S

up

erco

nd

uct

ivit

y R

esea

rch

-

Un

iver

sity

of

Cam

bri

dge

B.A.Glowacki

Bi 2212 Fault Current Limiter

Ap

pli

ed S

up

erco

nd

uct

ivit

y R

esea

rch

-

Un

iver

sity

of

Cam

bri

dge

B.A.Glowacki

Bi2212 round wire vs Composite Reaction Texturing

(a)259-filamentary Bi2212 round wire (a) as drawn; (b) after heat treatment (c) EDAX atomic mapping of Bi (darker area) of a fragment of heat treated wire;

Source of distortion of the Bi2212 filaments: Retrograde densification and intergrowth

(b) (c)

MgO whiskersBi-2212

(a)

(b)

A schematic cross section of Bi2212/MgO-fibre composite (a) earlier stage of nucleation during cooling down and (b) final microstructure. MgO-fibre can be envisaged to align 2D random in plane.

An SEM micrograph of a thermally etched cross section of CRT coating showing also the gold contact interface. (An end view of the MgO-fibre shown represent the MgO-f plane).

50nm

7Þ

5Þ

6Þ3Þ

3Þ

3Þ

5Þ

1Þ

TEM of the melt textured Bi2212 (Composite Reaction Textured)

Ap

plie

d

Su

per

con

du

ctor

s

Ap

pli

ed S

up

erco

nd

uct

ivit

y R

esea

rch

-

Un

iver

sity

of

Cam

bri

dge

B.A.Glowacki

Oxygen doping optimisation of Coated Bi2212 conductor

0

200

400

600

800

10-7 10-6 10-5 10-4 10-3 10-2 10-1 100

x=8.21, Tc=94Kx=8.22, Tc=90Kx=8.23, Tc=89Kx=8.24, Tc=82Kmelting

Co

olin

g te

mp

era

ture

o C

pO2 (atm)

Bi-2212 melting

Bi-2212 unstable

(2) (1)

Schematic representation of the temperature and oxygen partial pressure dependence of the oxygen content, x, in Bi2Sr2CaCu2Ox phase; (1) sample slowly cooled under 0.21atm partial oxygen pressure, SC, and (2) sample SC(pO2).

High-resolution transmission electron microscopy (HRTEM) images of low angle grain boundaries recorded from individual grains of: (a) a slowly cooled conductor under constant oxygen partial pressure of 0.21 atm, SC; (b) conductor cooled under under monotonically reduced partial pressure of oxygen SC(pO2).

(a)(b)

0 100

5 103

1 104

1.5 104

2 104

2.5 104

65 70 75 80 85 90

SCSC(pO2)

Tran

sport

Jc A

cm

-2Temperature (K)

The temperature dependence of the transport Jc characteristics for tape SC(pO2) and SC.

Ap

plie

d

Su

per

con

du

ctor

sT T

0 a log

10( pO

2)

To ensure that x=8.21 can be retain during the slow cooling procedure, the constant parameters of temperature, To and a, were chosen as To=870ºC and

a=60ºC.