Thirteenth International Workshop on Ceramic Breeder Blanket Interactions 30 Nov 2 Dec 2005 Fess Parker DoubleTree Resort, Santa Barbara, CA, USA Investigation of Fabrication Technologies for Japanese ITER Test Blanket Module T. Hirose, Y. Nomoto, M. Enoeda and M. Akiba Blanket Technology Group
Fabrication process of F82H thin tubes for TBM was tested. The pretreatment condition of F82H was investigate.
Contents Background Trial of tube milling for TBM Pretreatment effects on F82H HIP joint Summary
Japanese WCSB TBM Armor First wall Side wall Breeding layer Back wall WCSB TBM Structural material is reduced activation ferritic/martensitic steel, F82H.
Reduced activation ferritic/martensitic steel, RAF/M RAF/M is a kind of 9Cr heat resisting steel. T91: 9%Cr-1%Mo-Nb, V F82H: 8%Cr-2%W -Ta, V Technically matured in boiler and pressure vessel.
Commercial 9%Cr steel The steel is usually used for thin wall structure. It is usually jointed by welding.
Pipe list for WCSB-TBM Dimension Parts Name Thick. OD Length (mm) (mm) (mm) First wall 11mm square 1.5 11 2850 Side wall 13.6mm square 1.8 13.6 1690 BW purge gas inlet 25.4mm cylinder 3.5 25.4 200 BW coolant inlet 101.6mm cylinder 12.7 101.6 200 Membrane panel 11mm cylinder 1 11 1740 Connecting pipe to BW 34mm cylinder 4.5 34 500 Cable conduit 70mm cylinder 10 70 200 Cable conduit 13.8mm cylinder 3.4 13.8 300 Purge gas 10.5mm cylinder 1 10.5 600 Thin structure is required for TBR.
Fabrication of first wall Structure 25mm 5.5mm T plate 7.5mm T plate HIP joint 11mm x 1.5 T mm square tube The first wall consists of thin plates and thin square tubes. These pipe and plates are jointed by Hot Isostatic Pressing, HIP method.
Issues in TBM fabrication process Thick structure must be technically validated. Perfect HIP condition is required, because of its difficulty in nondestructive inspection.
Process of cold tube milling 150kg ingot Forging φ30 x 590 L rod 24pcs Drilling φ30 x 5 T x 590 L tube Annealing Cold rolling This method is applied for fuel clad of LWR.
Dimensional change in cold rolling After the each path, the pipes were annealed at 1083K. φ15.8x1.5 T x 3.2m tubes were successfully milled. Neither bowing nor cracking occurred.
Hardness change in cold rolling Typical Hv of F82H Outer Inner Middle Vickers hardness tests were done on the cross section. Softened microstructure can be recovered by HIP process.
Thin cylinder tube φ30x5 T φ28x4.4 T φ26x3.9 T φ24x3.4 T φ22x2.8 T φ20x2.2 T φ18x1.8 T φ15.9x1.5 T In case of 9%Cr, φ30x5 T pipe is produced by hot extrusion. This method can be applied to future mass production.
Square tube fabrication by cold rolling 1 2 3 4 5 6 7 φ15.9x1.5 T cylindrical tube was cold-milled by seven rolls. The cross section was gradually deformed to square.
11x1.5 T square tube R<0.6 Width: 11±0.05mm Thick: 1.5±0.04mm R outer : <1.4mm R inner : <0.6mm Length: >3200mm R<1.4
11x1.5 T square tube 510 Width: 11±0.05mm Thick: 1.5±0.04mm R outer : <1.4mm R inner : <0.6mm Length: >3200mm 1740 First wall Total wall length is 2760mm
11x1.5 T square tube
F82H for TBM fabrication Dimension Weight/ Module Name Thick. Width/OD Length parts Quantity Weight Method (mm) (mm) (mm) (kg) (kg) 4mm T plate 4 600 2000 38 3 114 Hot rolling 9mm T plate 7.5 400 3000 71 2 142 Hot rolling 12mm T plate 12 600 3000 170 10 1700 Hot rolling 16mm T plate 16 400 2000 101 8 808 Hot rolling 50mm T plate 50 400 1000 158 4 632 Hot rolling 92mm T plate 92 400 2000 580 2 1160 Hot rolling 11mm square 1.5 11 3000 3 60 180 Billet & cold rolling 11mm cylinder 1 11 2000 4 90 360 Billet & cold rolling 13.6mm square 1.8 13.6 2000 3 40 120 Billet & cold rolling 13.8mm cylinder 3.4 13.8 300 3 16 48 Billet & cold rolling 3.5mm cylinder 3.5 25.4 500 3 4 12 Billet & cold rolling 34mm cylinder 4.5 34 500 3 24 72 Billet & cold rolling 70mm cylinder 10 70 200 6 16 96 Welded pipe 101.6mm Cylinder 12.7 101.6 500 20 4 80 Welded pipe Total: 5500kg
Summary of Pipe and Plates for Each parts and plates can be provided by labo-scale melting (150-300kg) except for back wall (580kg). TBM Thin tube can be provided by cold rolling method. Fabrication process of each parts has been validated.
Effects of pre-treatment conditions on F82H HIP joint
Conventional HIP process Parts Degassing for parts polishing (R max 44->4μm) assembling 200 HIP HIP 300 Square channel canning Degassing inside can (10-3 Pa @ 1273K) HIP PHHT (1313Kx 150MPa x 2hr.) Effects of pretreatment condition was studied.
Tensile properties of HIP joint Degassing for parts: 573K HIP: 1373K x 150MPa x 2h. PHHT: 1233K x 0.5h + 1023K x 1.5h Tensile properties of HIP joint seemed to be same as those of base metal.
Impact properties of HIP joint Degassing inside can is required to complete HIP joint.
Recovery of impact properties by thermal aging Decrease in absorbed energy was caused by surface oxide. Removing oxide and diffusion of oxide are important process for HIP.
Summary of HIP joint Tensile tests was insensitive to HIP joint. Appropriate evaluation method must be established. Surface oxide had significant damage on joint properties. Surface oxide should be removed at pretreatment process, however, thermal aging after HIP could be a solution to recover the impact property.