International Conference on Fast Reactors and Related Fuel Cycles 2013, Paris, France Fabrication and Evaluation of SFR Cladding Tubes Sung Ho Kim, J.H. Baek, J.H. Kim, C.B. Lee Next Generation Fuel Development Division Korea Atomic Energy Research Institute
Outline 1. Introduction 2. Status of SFR Cladding Tube Development Advanced cladding materials development Cladding tube fabrication Evaluation of cladding tube 3. Future Works 4. Summary 2
FM Steels for SFR Cladding Tubes Ferritic/martensitic steels High thermal conductivities Low expansion coefficients Excellent irradiation resistance to a void swelling Handling Socket Duct Fuel Pin Upper End Plug Wire Wrap Upper Gas Plenum Cladding materials Development of FM steels Basic composition 9Cr-2W steel Nose Piece Coolant Port Fuel Slug Lower End Plug and Shielding 3
Core Environment & Design Requirements Core Environment Inlet temperature : 390 o C Outlet temperature : 545 o C Fuel temperature : > 650 o C 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% 4
Target of SFR Cladding Tubes Development of new cladding having higher creep rupture strength Development of cladding tube fabrication process Max. allowable temp. of cladding tube Max. fluence of cladding tube KALIMER 600 New Target 630 o C Above 650 o C 200 dpa > 200 dpa 5
Strengthening mechanism of FM steels Solid Solution Strengthening Precipitation Strengthening W, Mo, V, Nb, Ta, B, C, N, 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 VIII Period hydrogen 1) Cr 5) B helium 1 1 2) Mo, W, Re 6) Si, Mn 2 H 3) V, Nb, Ta, Ti 7) Ni, Cu, Co He 5) C, N 8) Al, P, S 1.0079 4.0026 2 lithium beryllium boron carbon nitrogen oxygen fluorine neon 3 4 5 6 7 8 9 10 Li Be B C N O F Ne 6.94 9.01218 10.81 12.011 14.0067 15.999 18.998403 20.18 3 4 5 6 7 sodium magnesium aluminium silicon phosphorus sulfur chlorine argon 11 12 13 14 15 16 17 18 Na Mg Al Si P S Cl Ar 22.98977 24.305 26.98154 28.086 30.97376 32.07 35.453 39.948 potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 K 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 83.8 rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe 85.468 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 131.3 caesium barium 57-71 hafnium tantalum tungsten rhenium osmium iridium platinum gold mercury thallium lead bismuth polonium astatine radon 55 56 * 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 Cs 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 darmstadtiu m roentgenium ununbium ununtrium ununquadiu m ununpentium ununhexium ununseptium ununoctium 87 88 ** 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 Fr 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]*** 6
Alloy Design Batch 0 Batch 1 Batch 2 B001 (1 alloy) : Ref. alloy 1. B001( 1종 ): 기준합금 9Cr-2W00 2. B002, B002~B003(3 3 (2 alloys) 종 ):B 첨가 : B 영향 9Cr-2WB1 9Cr-2WB2 3. B004~5 B004~B005(2 alloys) 종 ):C 최적화 : C 9Cr-2WC1 9Cr-2WC2 4. B006~8 B006~B008(3 alloys) 종 ):V/Nb : V, 최적화 Nb 9Cr-2WVNb1 9Cr-2WVNb2 9Cr-2WVNb3 5. B009~B010(2 B009~10 alloys) 종 ):Ta 첨가 : Ta 영향 9Cr-2WVNbTa1 9Cr-2WVNbTa2 B101 (1 alloy) : Ref. alloy 1. B101(1종 ): 기준합금 9Cr-2WVNbTaB1 2. B102~B104(4종 ):V, Nb, Ta 함량 2. B102~4 (4 alloys) : V, Nb, Ta 최적화 9Cr-2WVNbTaB2 9Cr-2WVNbTaB3 9Cr-2WVNbTaB4 3. B105 (1종(1 ):C, alloy) N 최적화 : C, N 9Cr-2WVNbTaB5 4. B106~B110(5 B106~10 종 alloys) ): Ti, Zr, : Pd, Pt, Nd 영향평가Ti, Zr, Pd, Pt, Nd 9Cr-2WVNbTiB 9Cr-2WVNbZrB 9Cr-2WVNbPdB 9Cr-2WVNbPtB 9Cr-2WVNbNdB 1. B201 (1 alloy) : reference alloy 9Cr-0.5Mo2W-VNbTa-00 2. B202~B203 (2 alloys) : Ta effect 9Cr-0.5Mo2W-VNbTa-N1 9Cr-0.5Mo2W-VNbTa-N2 3. B204~B205 (2 alloys) : V effect 9Cr-0.5Mo2W-VNbTa-V1 9Cr-0.5Mo2W-VNbTa-V2 4. B206~B208 (3 alloys) : W, N, B, V effect 9Cr-0.5Mo3W-VNbTa-00 9Cr-0.5Mo2W-VNbTa-B1 9Cr-0.5Mo2W-VNbTa-VB1 5. B209~B210 (2 alloys) : P effect 9Cr-0.5Mo2W-VNbTa-P1 9Cr-0.5Mo2W-VNbTa-P2 6. B211~B213 (3 alloys) : Zr, Pt, Ge, Cu effect 9Cr-0.5Mo2W-VNbTa-Zr 9Cr-0.5Mo2W-VNbTa-Pt 9Cr-0.5Mo2W-VNbTa-GeCu 7. B214~B215A (3 alloys) : Nb, Ta, N effect 9Cr-0.5Mo2.2W-3VNb 9Cr-0.5Mo2.2W-3VNbTa 9Cr-0.5Mo2.2W-3VNbTaN 7
Stress (MPa) Advanced Cladding Materials Development Alloy design and manufacturing 38 alloys in 3 batches Vacuum induction melting (30kg) Hot rolling (thickness : 15mm) Heat treatment (normalizing at 1050 o C, tempering at 750 o C) Performance tests Microstructure examination Sodium compatibility tests Creep/tensile tests CRS of new alloy improved by more than 35 % from HT9 9Cr-2W-0.05Ta-0.08N-0.006B 9Cr-2W-0.05Ta-0.02N-0.15B 180 160 140 120 650 o C 100 100 1000 10000 Time to Rupture (hr) HT9 T92 PNC-FMS KAERI 8
Fabrication 피복관예비시제품 of HT9 Cladding 제조 Tube Hollow billet VIM (1 ton ingot) Hot forging at 1200 o C Machining (OD 180mm) Mother tube fabrication Hot extrusion (OD 54mm) Pilgering & Drawing Intermediate HT (OD 19mm) Tube fabrication Drawing (4 times) Intermediate heat treatment Final heat treatment Cladding tube (OD 7.4mm, T 0.56mm) 1 ton ingot Drawing Hot extrusion Heat treatment Intermediate tube Cladding tube 9
Microstructure of HT9 Cladding tube Dimension - Outer diameter : 7.427 + 0.05 mm - Inner diameter : 6.318 + 0.05 mm - Thickness : 0.549 mm Microstructure Martensite + Delta ferrite Surface roughness - Outside : 0.441 μm - Inside : 0.111 μm Straightness < 10 μm 10
Tensile Test of Cladding Tubes Ref.) W.L. Bell, et al., GE, Proc. of Topical Conf. on Ferritic Alloys for use in Nucl. Energy Technologies (1983) Ref.) W.L. Bell, et al., GE, Proc. of Topical Conf. on Ferritic Alloys for use in Nucl. Energy Technologies (1983) Test temperature : RT ~ 700 o C Gr.92 tube had higher yield and ultimate tensile strength than HT9 tube. Total elongation of Gr.92 tube was a little lower than that of HT9 tube. HT9 cladding tube had tensile properties similar to the data in the literature. 11
Burst Test of Cladding Tubes Test conditions Burst test was performed by pumping gas up to burst. Test results Ultimate hoop stress HT9 : 1135MPa (R.T), 488MPa (658 o C) Gr.92 tube had a lower UHS than HT9 tube at elevated temperature. 658 614 562 452 RT 12
Hoop stress (MPa) Creep Test of HT9 Cladding Tube Test conditions Test temperature : 650 o C Applied hoop stress : 120MPa to 216MPa Test results Time to rupture of HT9 tube 4hrs (216MPa), 9hrs (194MPa) 36hrs (162MPa), 173hrs (140MPa), 524hrs (120MPa) HT9 cladding tube had creep rupture strength similar to the data 240 220 200 180 160 HT9 (KAERI) 1) HT9 (KAERI-Round bar) 2) HT9 (EP0287710A2) 3) HT9 (EP0287710A2) 4) HT9 (EP0287710A2) 5) in the literature. Creep test of Gr.92 cladding tube is on-going 140 120 100 80 60 1) 1038C, 5min 760C, 30min 2) 1050C, 30min 750C, 2hr 3) 1100C, 5min 760C, 30min 4) 1040C, 5min 650C, 2hr 5) 1040C, 5min 704C, 2hr 10 100 1000 10000 Rupture time (hr) 13
Final Heat Treatment 650C UTS (MPa) 650C YS (MPa) Heat treatment conditions Normalizing : 950 ~ 1100 o C x 30min Tempering : 700 ~ 800 o C x 1hr Tensile test results Tensile test : 650 o C Future works 260 240 220 200 180 160 950C 1000C 1050C 1100C Creep test 740 750 760 770 780 280 260 240 HT9 (AR) 950C 1000C 1050C 1100C Tempering temp. ( o C) 220 200 180 160 740 750 760 770 780 Tempering temp. ( o C) AR HT9 : 239.11 14
Core Components Development Plan 연구내용 Item 2단계 ( 실증로 1 st 개념설계 phase ) 차기단계 2 nd phase ( 표준설계 ) 차기단계 3 rd phase ( 표준설계 ) 2012-2014 ( 12-16) (2015-2016) ( 12-16) (2017-2020) Cladding tube Cold working process Heat treatment conditions Fabri. cladding tube Design of Irra. test rig Fabr. of rig Out-of-pile test (creep, tensile, impact, fracture toughness) Fast reactor irradiation test PIE (swelling, creep etc.) Wire Wire design Fabri. wire Fabr. of rig Out-of-pile test of wire (tensile, creep, impact etc.) Fast reactor irradiation test and PIE Duct design Fabri. duct Out-of-pile test of duct (tensile, creep, impact etc.) Duct Duct fabri. process Fabr. of rig Fast reactor irradiation test of duct PIE (impact, fracture toughness etc.) Assembly parts Design of assembly parts Assembly parts fabrication process Fabri. Assembly parts Out-of-pile test 15
Irradiation Test Plan of Cladding Tube Irradiation test : Oct. 2014 Specimens HT9M1 : 9Cr-2W-V-Nb-B (cladding) HT9M2 : 9Cr-2W-V-Nb-N (cladding) T91 : Modified 9Cr-1Mo (duct) HT9 (cladding & duct) Irradiation temperature : 390 o C, 545 o C, 650 o C Fluence : 20dpa, 80dpa, 160dpa, 200dpa 16
Post Irradiation Test Plan of Cladding Tube PIE items Nondestructive tests Visual inspection Irradiation swelling Irradiation creep (pressurized cladding tube) Destructive tests (4 set) Mechanical test (Tension, Charpy impact, fracture toughness, Compact tension) Microstructure (dislocation, precipitation, void) 17
Summary Development of advanced FM steels 9Cr-2W-TaVNbB Fabrication and evaluation of cladding tubes HT9 and Gr.92 cladding tube fabrication Creep, tensile, burst, and microstructure HT9 cladding tube fabricated in Korea showed similar mechanical properties with the data in the literature. Future works Fabrication of cladding tubes with new alloys Performance of out-of-pile test Fast neutron irradiation test 18
Thank you for your attention! 19