development of sfr fuel cladding tube materials...heat treatment – normalizing : 1050 oc x 1 hour...
TRANSCRIPT
1 FR09, Kyoto, 7-11 December 2009
Development of SFR Fuel Cladding Tube Materials
International Conference on Fast Reactors and Related Fuel Cycles (FR09), Kyoto, Japan
8 December 2009Sung Ho Kim, Chan Bock Lee, and Dohee Hahn
2 FR09, Kyoto, 7-11 December 2009
Outline
Core Environment of SFRISFR Fuel Cladding Development ProgramIIAlloy Design for SFR Cladding MaterialsIIIEvaluation of New AlloysIVEvaluation of Fabrication ProcessVSummaryVI
3 FR09, Kyoto, 7-11 December 2009
Core Environment of SFRI
I.1 Fuel Rod and Assembly I.2 Core Environment & Design
Requirements for Cladding Tube
4 FR09, Kyoto, 7-11 December 2009
I.1 Fuel Rod & AssemblyHandling Socket
Duct
Nose Piece
Coolant Port
Fuel Pin
� Fuel cladding tube dimension– Outer diameter : 8.5 mm– Thickness : 0.53 mm– Length : 3500 mm
� Fuel assembly– No. of rod : 271– No. of fuel rod : 267– Length : 4500 mm
� SFR fuel materials– Fuel : Metallic– Cladding material : FM steel– Duct material : FM steel
5 FR09, Kyoto, 7-11 December 2009
�Core Environment– Inlet temperature : 370oC– Outlet temperature : 545oC– Fuel temperature : 650oC– Fast neutron fluence : 200 dpa– Hoop stress (end of life) : 70MPa– 3-4 cycles (1 cycle : 18 month) : 50,000 hrs
�Design Requirements of Cladding Tube– Thermal strain : < 1%– Total strain : < 3%– Swelling : < 5%
I.2 Core Environment & Design Requirements
6 FR09, Kyoto, 7-11 December 2009
SFR Fuel Cladding Development ProgramII
II.1 TargetII.2 Long-term Development PlanII.3 Short-term Development Plan
7 FR09, Kyoto, 7-11 December 2009
II.1 Target
KALIMER 600 New TargetMax. allowable temp. of cladding tube 630oC Above 650oC Max. fluence of cladding tube 200 dpa 250 dpaLimitation in cladding temp. by eutectic melting (oC)
650oC – 700oC No. (Apply barrier to cladding tube)
�Development of new cladding having higher creep rupture strength �Development of barrier materials for applying to
cladding tube
8 FR09, Kyoto, 7-11 December 2009
II.2 Long-term Development Plan’’07~07~’’0808 ’’09~09~’’1010 ’’11~11~’’1212 ’’13~13~’’1414 15~15~’’1616 17~17~’’1818 ’’19~19~’’2020 ’’21~21~’’2222 ’’23~23~’’2424 ’’25~25~’’2626 ’’27~27~’’2828
SFRSFR
SFR Fuel CladdingSFR Fuel Cladding
Develop. Key tech.Develop. Key tech. Verification tech.Verification tech. Demonstration tech.Demonstration tech. Commercialization tech.Commercialization tech.
Develop. New FMS claddingDevelop. New FMS cladding
Verifi. of new FMSVerifi. of new FMS
Manufac. FM steel cladding & out-of-pile test
Manufac. FM steel cladding & out-of-pile test
In-pile test of FM steel claddingIn-pile test of
FM steel claddingCommercialization of new FM steel
Commercialization of new FM steel
Basic studyBasic study
Develop. of evaluation technologyfor out-of-pile performance
Develop. of evaluation technologyfor out-of-pile performance
Cladding Manufac. Tech.Cladding Manufac. Tech.
Develop. of evaluation technologyfor in-pile performance
Develop. of evaluation technologyfor in-pile performance
Develop. ODS steelDevelop. ODS steel Manufac. ODS steel cladding & out-of-pile testManufac. ODS steel
cladding & out-of-pile testIn-pile test of
ODS steel claddingIn-pile test of
ODS steel claddingCommercialization
of ODS steel Commercialization
of ODS steel
Gen IV SFR Advanced concept
design
Gen IV SFR Advanced concept
designPreliminary designPreliminary design Detailed designDetailed design
ConstructionConstruction
Gen IV SFRConcept design
Gen IV SFRConcept design
Gen IV SFRStandard design
Gen IV SFRStandard design
9 FR09, Kyoto, 7-11 December 2009
II.3 Short-term Development Plan
� Develop. evaluation technology• Evalu./analysis tech for creep test • Evalu./analysis tech for cladding/sodium compatibility test
� Fabrication of HT9 tube • Evaluate fabrication process• Perform mechanical test with HT9 cladding tube
Patent fornew cladding
materialMaterial standard
for cladding
2007200720072007 2011201120112011
Development of SFR Fuel Key Technology
Manufac. of cladding/sodium compatibility tester
� Basic studies• Basic properties• Creep deformation map• Irradiation effects
� Verifi. candidate cladding materials (Pilot scale )
• Verifi. of creep properties• Verifi. of cadding/sodium compatibility
• Production of material database
� Basic study for cladding fabrication• Analysis fabrication technology• Analysis fabrication process
Database for new FMS
� Develop. candidate claddingmaterials (Lab scale )
• Analysis of status (patent map)• Design & testing of new alloy• Selection of candidate claddingmaterial
Basic database
Performancedatabase
Fabricationprocess
Newcladding materials for high burnup
Cladd./sodium Compa. test
10 FR09, Kyoto, 7-11 December 2009
Alloy Design for SFR Fuel Cladding MaterialsIII
III.1 Evaluation of Minor Alloying Elements III.2 Strengthening Mechanism of FM SteelsIII.3 Alloy Design III.4 Fabrication Process
11 FR09, Kyoto, 7-11 December 2009
III.1 Evaluation of Minor Alloying Elements Group 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
I II III IV V VI VII VIIIPeriod
hydrogen helium
1 2H He
1.0079 4.0026lithium beryllium boron carbon nitrogen oxygen fluorine neon3 4 5 6 7 8 9 10Li Be B C N O F Ne6.94 9.01218 10.81 12.011 14.0067 15.999 18.998403 20.18
sodium magnesium aluminium silicon phosphorus sulfur chlorine argon11 12 13 14 15 16 17 18Na Mg Al Si P S Cl Ar
22.98977 24.305 26.98154 28.086 30.97376 32.07 35.453 39.948potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr
39.0983 40.08 44.95591 47.867 50.9415 51.996 54.93805 55.84 58.9332 58.693 63.55 65.4 69.723 72.6 74.9216 79 79.904 83.8rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe85.468 87.62 88.9058 91.22 92.9064 95.94 [97.9072] 101.1 102.9055 90 107.868 112.41 114.82 118.71 121.76 127.6 126.9045 131.3caesium barium 57-71 hafnium tantalum tungsten rhenium osmium iridium platinum gold mercury thallium lead bismuth polonium astatine radon55 56 * 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86Cs Ba Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn
132.9054 137.33 178.5 180.9479 183.84 186.207 190.2 192.22 195.08 196.9666 200.6 204.383 207.2 208.9804 [208.9824] [209.9871] [222.0176]francium radium 89-103 rutherfordiu
m dubnium seaborgium bohrium hassium meitnerium darmstadtium roentgenium ununbium ununtrium ununquadiu
m ununpentium ununhexium ununseptium ununoctium87 88 ** 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118Fr Ra Rf Db Sg Bh Hs Mt Ds Rg Uub Uut Uuq Uup Uuh Uus Uuo
[223.0197] [226.0254] [263.1125] [262.1144] [266.1219] [264.1247] [269.1341] [268.1388] [272.1463] [272.1535] [277] [284] [289] [288] [292] [291]*** [294]***
1 3) V, Nb, Ta, Ti5) C, N
1) Cr2) Mo, W, Re
5) B
3
4
5
6
7
6) Si, Mn7) Ni, Cu, Co8) Al, P, S
2
1) Cr: Precipitation hardening2) Mo, W, Re: Solid solution hardening3) V, Nb, Ta, Ti: Precipitation hardening4) C, N: Precipitation hardening5) B: Stabilization of precipitates6) Si, Mn: Stabilization of precipitates7) Ni, Cu, Co: Stabilization of microstructure8) Al, P, S: Stabilization of microstructure
Evaluation Evaluation of base dataof base data
• Crystal structure/atomic radius• valence/Electronegativity/MP• nucleus embrittlement• Formation of δδδδ-ferrite• Phase transformation temp. (Ms, A1)
12 FR09, Kyoto, 7-11 December 2009
III.2 Strengthening Mechanism of FM Steels
+ Mo + W+ W
Solid SolutionStrengtheningSolid SolutionStrengthening
+ V + Nb+ V + Nb C, N, B Ta, Zr, Ti
PrecipitationStrengtheningPrecipitation
Strengthening
Strengthening mechanisms of FMS SteelsStrengthening mechanisms of FMS Steels
•• Effect of B additionEffect of B addition•• Optimization of Optimization of C C andand NN•• Optimization of Optimization of NbNb,, VV•• Effect of Ta additionEffect of Ta addition•• Effect of Effect of ZrZr and and TiTi
13 FR09, Kyoto, 7-11 December 2009
III.3 Alloy Design � Chemical compositions
� Specimen manufacturing– Vacuum Induction Melting (Ingot size : 30kg)– Hot rolling (1150oC)
� Heat treatment– Normalizing : 1050oC x 1 hour– Tempering : 750oC x 2 hours– Air cooling was applied during all the heat treatment.
“9Cr-2W-Nb-Ta-V2BEffect of C and N concentration 9Cr-2W-Nb-Ta-V1-C1-N1C
Effect of Ti 9Cr-2W-Nb-V-TiDEffect of Zr9Cr-2W-Nb-V-ZrE
Effect of V concentration 9Cr-2W-Nb-Ta-V1ARemark Nominal composition ID
14 FR09, Kyoto, 7-11 December 2009
III.4 Fabrication Process
�Cold rolling and heat treatment– Plate : normalized at 1050oC for one hour, tempered at 550oC for 2 hours– Cold rolled from 4 mm to 1 mm– One time cold rolling :
• Reduction ratio : 75%• Heat treatment : 750oC for 30 min
– Three times cold rolling• Reduction ratio : 33% or 44%• Heat treatment : 750oC for 10 min
15 FR09, Kyoto, 7-11 December 2009
Evaluation of New AlloysIV
IV.1 Phase Equilibrium DiagramIV.2 Mechanical Properties
16 FR09, Kyoto, 7-11 December 2009
IV.1.1 Phase Equilibrium Diagram�Phase equilibrium of Alloy A & B
– Alloy A : high vanadium steel– Alloy B : low vanadium steel– Equilibrium phases : M23C6, MX, BN and
Laves phase– Ae1 temperature : 805oC and 780oC in
alloy A and B• Alloy A can be tempered at higher
temperature.• More stable precipitates may be formed.• Creep resistance of Alloy A may be
improved.– V-rich MX phases
• Formed in Alloy A• Not appeared in Alloy B
0
5
10
15
20
25
30
35
40
45
50
10-3
BPW(
*)
300 400 500 600 700 800 900 1000 1100 1200 1300TEMPERATURE_CELSIUS
DATABASE:TCFE5 W(CR)=9.33E-2, W(MO)=5.21E-3, W(W)=1.95E-2, W(V)=2.96E-3, W(NB)=5.2E-4, W(C)=7E-4, W(SI)=7E-4, W(MN)=4.44E-3, W(NI)=4.74E-3, W(N)=6E-4, W(B)=1.6E-4, P=1E5, N=1.;
2
2:T-273.15,BPW(BN_HP4)
1
1:T-273.15,BPW(BCC_A2)
24
4:T-273.15,BPW(FCC_A1#2)
2 42 45
5:T-273.15,BPW(FCC_A1#4)
24
524
5 6
6:T-273.15,BPW(M23C6)
245
6
24
5
7
7:T-273.15,BPW(LAVES_PHASE_C14)
6
24
7
6
Ferrite Austenite
A e1
A e3
Delta
Mas
s fra
ctio
n
L a v e s
M23C6
MX
Temperature, oC
BN0
5
10
15
20
25
30
35
40
45
50
10-3
BPW(
*)
300 400 500 600 700 800 900 1000 1100 1200 1300TEMPERATURE_CELSIUS
DATABASE:TCFE5 W(CR)=9.33E-2, W(MO)=5.21E-3, W(W)=1.95E-2, W(V)=2.96E-3, W(NB)=5.2E-4, W(C)=7E-4, W(SI)=7E-4, W(MN)=4.44E-3, W(NI)=4.74E-3, W(N)=6E-4, W(B)=1.6E-4, P=1E5, N=1.;
2
2:T-273.15,BPW(BN_HP4)
1
1:T-273.15,BPW(BCC_A2)
24
4:T-273.15,BPW(FCC_A1#2)
2 42 45
5:T-273.15,BPW(FCC_A1#4)
24
524
5 6
6:T-273.15,BPW(M23C6)
245
6
24
5
7
7:T-273.15,BPW(LAVES_PHASE_C14)
6
24
7
6
Ferrite Austenite
A e1
A e3
Delta
Mas
s fra
ctio
n
L a v e s
M23C6
MX
Temperature, oC
BN
0
5
10
15
20
25
30
35
40
45
50
10 -3BP
W(*)
300 400 500 600 700 800 900 1 000 1100 1200 1300
TEM PERATUR E_CELS IU S
TH ERMO-CA LC (2009. 03.02:13.50 ) : DAT ABASE:TCF E5 W (CR) =9E-2 , W (MO) =5 .27E- 3, W (W )=2 .2E-2 , W (V )= 1. 1E-3 , W (NB)= 5.3E -4, W (C)=6 .6E -4, W (S I) =3.1E- 4, W (MN)= 4.43E-3, W (NI)= 4.85E -3, W (N)=7E-4 , W (B)= 1 .8E- 4, P=1E5, N= 1. ;
2
2:T-273.15,BPW(BN_HP4)
224
4:T-273.15,BPW(F CC_A1#3)
25
5:T-273.15,BPW(F CC_A1#2)
424 2542424
1
1:T-273.15,BPW(BCC_A2)
242 4
6
6:T-273.15,BPW(M23C6 )
24
6
24
7 7:T-273.15,BPW(L AVES _P HASE_C14)
6
Ferrite Austenite
A e1
A e3
Delta
Mas
s fr
actio
n
Lav es
M23C6
MX
Temperature, oC
BN0
5
10
15
20
25
30
35
40
45
50
10 -3BP
W(*)
300 400 500 600 700 800 900 1 000 1100 1200 1300
TEM PERATUR E_CELS IU S
TH ERMO-CA LC (2009. 03.02:13.50 ) : DAT ABASE:TCF E5 W (CR) =9E-2 , W (MO) =5 .27E- 3, W (W )=2 .2E-2 , W (V )= 1. 1E-3 , W (NB)= 5.3E -4, W (C)=6 .6E -4, W (S I) =3.1E- 4, W (MN)= 4.43E-3, W (NI)= 4.85E -3, W (N)=7E-4 , W (B)= 1 .8E- 4, P=1E5, N= 1. ;
2
2:T-273.15,BPW(BN_HP4)
224
4:T-273.15,BPW(F CC_A1#3)
25
5:T-273.15,BPW(F CC_A1#2)
424 2542424
1
1:T-273.15,BPW(BCC_A2)
242 4
6
6:T-273.15,BPW(M23C6 )
24
6
24
7 7:T-273.15,BPW(L AVES _P HASE_C14)
6
Ferrite Austenite
A e1
A e3
Delta
Mas
s fr
actio
n
Lav es
M23C6
MX
Temperature, oC
BN
Alloy A
Alloy B
17 FR09, Kyoto, 7-11 December 2009
Mas
s fra
ctio
n
IV.1.2 Phase Equilibrium Diagram
�Phase equilibrium of Alloy C– Carbon concentration : decrease– Nitrogen concentration : increase– Ae1 temperature : 780oC– Mass fraction of M23C6 precipitates : reduce in Alloy C– Mass fraction of MX precipitates : increase in Alloy C
18 FR09, Kyoto, 7-11 December 2009
IV.2.1 Tensile Properties
�Tensile test results– Tensile test temperature : 650oC– V effect
• Low V alloy : higher yield and tensile strengths– C & N effect
• Low C & high N alloy : higher yield and tensile strengths – Ti of Zr effect
• Zr addition : more effective in improving yield and tensile strengths
0 200 400 600 8000
200
400
600
800
Stren
gth (M
Pa)
Test Temperature (oC)
Alloy A, YS Alloy B, YS Alloy A, TS Alloy B, TS
0 200 400 600 800
200
400
600
800
Stren
gth (M
Pa)
Test Temperature (oC)
Alloy A, YS Alloy C, YS Alloy A, TS Alloy C, TS
0 200 400 600 800200
400
600
800
Stren
gth (M
Pa)
Test Temperature (oC)
Alloy D, YS Alloy E, YS Alloy D, TS Alloy E, TS
19 FR09, Kyoto, 7-11 December 2009
IV.2.2 Creep Properties
�Creep rupture test results– Creep test temperature : 650oC– Applied stress : 120 ~ 150 MPa– V effect
• Low V alloy : higher creep rupture strength• Perform the creep test at low stress levels
– C & N effect• Low C & high N alloy : lower creep rupture strength
– Ti or Zr effect• Zr bearing alloy : higher creep rupture strength
10 100 1000 10000100
120
140
160
180
Appli
ed Lo
ad (M
Pa)
Time to Rupture (hrs)
Alloy A Alloy B
10 100 1000 10000100
120
140
160
180
Appli
ed Lo
ad (M
Pa)
Time to Rupture (hrs)
Alloy A Alloy C
100 1000 10000100
120
140
160
180
Appli
ed Lo
ad (M
Pa)
Time to Rupture (hrs)
Alloy D Alloy E
20 FR09, Kyoto, 7-11 December 2009
IV.2.3 Creep Rupture Elongation
100 110 120 130 140 150 1600
10
20
30
40
50
Ruptu
re Elo
ngati
on (%
)
Applied Load (MPa)
Alloy A Alloy B Alloy C Alloy D Alloy E
�Creep rupture elongation– V effect
• High V alloy : higher creep rupture elongation– C & N effect
• Low C & high N alloy : lower creep rupture elongation– Ti or Zr effect
• Similar creep rupture elongation– Creep rupture elongation : 15 ~ 25%, not changed with applied load
21 FR09, Kyoto, 7-11 December 2009
Evaluation of Fabrication ProcessV
V.1 MicrostructureV.2 Mechanical Properties
22 FR09, Kyoto, 7-11 December 2009
V.1.1 Microstructure - Matrix�Matrix microstructure
– Mother plate • Normalized at 1050oC for 1 hour• Tempered at 550oC for 2 hours• Typical tempered martensite structure• Lath width : 200 nm
– One time cold rolling• Reduction ratio : 75%• Tempered at 750oC for 30 min• Fully recrystallized ferritic structure• Excess strain energy stored through cold rolling • Average grain size : 3 um
– Three times cold rolling• Reduction ratio : 33-44%• Tempered at 750oC for 10 min• Recrystallized ferritic structure was observed.• Strain energy accumulated through first and second cold rolling : disappeared by intermediate heat treatment (a) Normalized
(b) One time cold rolling(c) Three times cold rolling
(a)
(b)
(c)
500nm
500nm
500nm
23 FR09, Kyoto, 7-11 December 2009
V.1.2 Microstructure - Precipitates
(a) Normalized(b) One time cold rolling(c) Three times cold rolling
(a)
(b)
(c)
�Precipitates microstructure– Mother plate
• M23C6 and V-rich MX fully dissolved• Tempering temperature was low enough to avoid the formation of M23C6 and V-rich MX
• Nb-rich MX phase• 85Nb-9V-4Cr-2W (at%)
– One time cold rolling• Nb-rich MX phase : originally contained in the steel before cold rolling
• M23C6 phase : 68Cr-25Fe-3Mo-4W (at%)• V-rich MX phase : 65V-12Nb-15Cr-8W• Size of V-rich MX : less than 100 nm• Size of M23C6 : relatively large
– Three times cold rolling• Nb-rich MX, V-rich MX, M23C6 phase • Fine and uniform precipitates• High density of dislocations: provide favorable nucleation site for precipitates
M23C6
500nm
500nm
500nm
24 FR09, Kyoto, 7-11 December 2009
V.2.1 Microhardness
100
200
300
400
500
FHT (750oC/30min+AC)
CR (1.0T, 75% Re)
Mother plate (4.0T)
CR: Cold rollingRe: Reduction ratio FHT: Final heat treatment AC: Air cooling
Vicke
rs ha
rdnes
s (Hv
)100
200
300
400
500
2nd IHT (750oC/10min+AC)
FHT (750oC/10min+AC)
1st CR (2.7T, 33% Re)
3rd CR (1.0T, 44% Re)
2nd CR (1.8T, 33% Re)
1st IHT (750oC/10min+AC)
Mother plate (4.0T)
CR: Cold rollingRe: Reduction ratio IHT: Intermediate heat treatment FHT: Final heat treatmentAC: Air cooling
Vicke
rs ha
rdnes
s (Hv
)
�Microhardness test results– Mother plate : 350 Hv– One time cold rolling
• Cold rolling : 419 Hv, heat treatment : 175 Hv• Significant softening : fully recrystallizedgrains
– Three times cold rolling• 1st cold rolling : 391 Hv, heat treatment : 344 Hv,
• Heat treatment recovered mechanical properties degraded during cold rolling.
• 2nd cold rolling : hardness increased, heat treatment : hardness decreased
• Final cold rolling & heat treatment : 246 Hv• Formation and growth of recrystallized grains
25 FR09, Kyoto, 7-11 December 2009
V.2.2 Tensile Properties
0
20
40
60
80
0
200
400
600
800
Stren
gth (M
Pa)
Yield Ultimate tensile
Three cold rollingsOne cold rollingFHT FHT2nd IHT1st IHT
Elongation
Elon
gatio
n (%)
�Tensile test results– Tensile test temperature : 650oC– One time cold rolling
• Yield, tensile strengths and elongation : 201 MPa, 235 MPa, and 35%
• Fully recrystallized structure– Three times cold rolling
• First heat treatment : 446 MPa, 544 MPa, and 17%
• Second heat treatment : yield and tensile strengths slightly reduced, elongation increased
• Third heat treatment : 368 MPa, 405 MPa, and 23%
• Partially recrystallized structure and finely distributed precipitates
26 FR09, Kyoto, 7-11 December 2009
Summary�Alloy Design and Evaluation
– Increase of V concentration caused the increase of mass fraction of V-rich MX particles.
– The high V steel showed lower yield, tensile and creep rupture strengths.– The high N and low C steel showed higher yield and tensile strengths, but revealed lower creep rupture strength than the low N and high C steel.
– The Zr addition was more effective than Ti addition in terms of yield, tensile and creep rupture strengths.
�Fabrication Process– The 75% cold rolling and the final heat treatment led to a transition to a fully recrystallized structure with a formation of large inhomogeneous M23C6carbides, resulting in a significant softening.
– However, three times cold rolling with an intermediate heat treatment after each cold rolling led to the formation of fine and uniform M23C6 carbides in a partially recrystallized structure, thus providing an enhanced tensile strength. These fabrication processes could be effective for fabricating a high strength ferritic/martensitic steels.