Role of Gas During Explosive Cladding

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31-10-13

TNO Prins MauritsLaboratoryDelft University ofTechnology

Role of Gas DuringExplosive la!!ing

I.M. Richardson

E.P. Carton

Y. van der Drift

H. van der Linde



31-10-13Richardson Carton van der Drift van der Linde

Outline

• "ntro!uction

• Mo!el of #eat Transfer

• Mo!el Pre!ictions

• Experi$ental Observations

• Te$perature Measure$ents

• onclusions

"ntro!uction




%asics& Operation

explosive

gap

b' During

detonato

r

Mediumexplosive

eta' %efore

c' En!

"ntro!uction




!1, "1 !0, "0

%asics& Effect of GaseousMe!iu$

• (lyer plate generates a shoc) *ave• The co$presse! gas *ill have a higher

te$perature

Ther$al effects + #eat transfer to the plate

Mechanical effects + Possible gap variation

"ntro!uction




#eat Transfer Mo!el

• Gas te$perature

• "nteraction ti$e of the

gas *ith the $etal

• #eat flux fro$ the gas

into the $etal&

• onservation ofEnergy&

)( interfacegas T T hq −= D i s t a n c e

gas

plate

temperature

!gas

!plate

#eat Transfer

T t

T C p

2∇=

∂

∂κ ρ




Gas Properties

#eat Transfer

1000 2000 3000 4000 5000 6000 7000 8000 9000

1

2

3

4

2000 4000 6000 8000

1

2

3

4

air

argon

k ( W / m / K

)

T(K)

T h e r m a l C o n d u c t i v i t y

( W m

- 1 K - 1 )

Temperature (K)

Argon

Air

1000 2000 3000 4000 5000 6000 7000 8000 9000

1

2

3

4

2000 4000 6000 8000

1

2

3

4

air

argon

k ( W / m / K

)

T(K)


( W m

- 1 K - 1 )

Temperature (K)

Argon

Air

1000 2000 3000 4000 5000 6000 7000 8000 9000

1

2

3

4

2000 4000 6000 8000

1

2

3

4

air

argon

k ( W / m / K

)

T(K)


( W m

- 1 K - 1 )

Temperature (K)

Argon

Air

1/6 1/4 V/V0

P/P0

P0, V0

d i a t o m

i c

m o n o a t o m

i c

1/6 1/4 V/V0

P/P0

P0, V0

d i a t o m

i c

m o n o a t o m

i c

1/6 1/4 V/V0

P/P0

P0, V0

d i a t o m

i c

m o n o a t o m

i c


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Gas Properties

#eat Transfer

• (or an i!eal gas

1

11

0

00 ,

a

u M

a

u M ==

ρ γ P

a =2

)1()1(1

212

0

2

02

1

1 −− −+=γ γ

γ M

M M

M # Mach $o%ux # &elocit'

ax # (peed of sound" # "ressureρ # Densit'γ # )dia*atic constantσ # 1st "ressurecoefficient

! # !emperature



Gas Properties

#eat Transfer

M # Mach $o%ux # &elocit'

ax # (peed of sound" # "ressureρ # Densit'γ # )dia*atic constantσ # 1st "ressurecoefficient

! # !emperature

σ 01 P P =

1)-(M1

2+1 2

1+=

γ

γ σ

02

1

2

1 T1)M(

)1)M-(+(2T 1

+=

γ

γ σ

o ρ γ

γ ρ

2

1

2

11

1)M-(2

1)M(

+

+=



• The length of the heate! gas region s is

*here uc is the collision point velocity an! us the shoc) front velocity

Gas Metal "nteraction

#eat Transfer

=

su x s cu-1



Mo!el Pre!ictions

0.00 0.04 0.08 0.12

400

800

1200

1600 Air vd = 3 x 103 m !1

0.01 "ar

0.1 "ar

0.5 "ar

1 "ar

T # m $ # r a % &

r # ( K )

'#$% (mm)

Mo!el



Mo!el Pre!ictions

Mo!el

0

500

1000

1500

2000

2500

000

500

0 0!02 0!04 0!06 0!0" 0!1 0!12 0!14 0!16 0!1" 0!2

Depth (mm)

T e m p e r a t u r e ( K )

#tain$ess #tee$Titanium

%o&&er

Titanium 'eta-21s

($uminium



Mo!el Pre!ictions

0.00 0.04 0.08 0.12

400

600

800

1000

= 105 a

Argon 3 km !1

Air

2.0 km !1

Air

2.5 km !1

Air 2.8 km !1

T # m $ # r a % & r # ( K )

'#$% (mm)

Mo!el

#i h - ! -t )



#igh,-pee! -trea) a$era"$age

Observations

Th l Eff t !



Ther$al Effects an!Microstructure

• Ti(e an! Ti(e.

inter$etallics in a

Ti/(e cla!!ing

• Effect of the

para$eters&

pressure an! type

of gas

Observations



Micrographs of a Ti/(e cla!!ing

"nter$etallics

GasType

0112 3ir

412 3rgon

512 6acuu$

Observations




"nter$etallics

GasType

0112 3ir

412 3rgon

512 6acuu$

Observations




"nter$etallics

GasType

0112 3ir

412 3rgon

512 6acuu$

Observations

T t M t



Te$perature Measure$ent&-tatic,$etho!

• "nterrupte! cla!!ing process• Measure time averaged temperature of a metal

foil heated *' shoc+ed gas

• se calorimetric principles to determine heat

transferred from the gas to the metal

#x$*oi#+

"ov#n$*aa%

o*,m##r

-%a*#n %ri$

ond#r$*aa%

x$*oiv#

/*,#r $*a%#

o*,m#r

Tin o$$#r +oi* Anvi**

a#

Te$perature

T t M t



Te$perature Measure$ent&-tatic,$etho!

• Experi$ental result on u,

foil

Te$perature

40.0

30.0

20.0

10.0

0.0

-10.0

-20.0

Time (s)

T e m p e r a t u r e (

° C )

Te$perature Measure$ent&



Te$perature Measure$ent&Dyna$ic,$etho!

• Thin ther$ocouple *ires• eat up fairl' homogeneousl' in thic+ness .d/

0 micron

Te$perature

Te$perature Measure$ent&



Te$perature Measure$ent&Dyna$ic,$etho!

"reliminar' result2

Te$perature

Time (μs)

V o l t a g e (

m V

-t'pe2 ! 4 1506C

ud 7 3 +m s-1


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onclusions

Ther$al effects&

• -i$ple $o!el sho*s

• Reduced surface temperature 8ith reduced gas pressure

• Reduced surface temperature 8ith monatomic gas

• Reduced surface temperature and increased thermal

penetration 8ith increased .metal thermal conductivit'

• Experi$ents in!icate

• 9as in the gap emits visi*le radiation during cladding

• :ntermetallic formation is consistent 8ith model predictions• Callorimetric .static and thin 8ire thermocouple .d'namic

temperature measurements can provide an indication of metal

surface temperatures%

onclusions

Documents

Role of Gas During Explosive Cladding