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SS hip joint materials for ITER shielding blankets
Fusion Engineering and Design 81 (2006) 631–637
Neutron irradiation effect on mechanical properties of SS/SS hip joint materials for ITER shielding blankets Hirokazu Yamada a,∗ , Satoshi Sato b , Kensuke Mohri b , Yoshiharu Nagao a , Fumiki Takada a , Hiroshi Kawamura b a
b
Japan Atomic Energy Agency (JAEA), 3607 Narita-Cho, Oarai-machi, Higashiibaraki-gun, Ibaraki-ken 311-1394, Japan Japan Atomic Energy Agency (JAEA), Naka-shi, lbaraki-ken 311-0193, Japan
Received 31 January 2005; received in revised form 21 July 2005; accepted 21 July 2005 Available online 20 December 2005
Abstract In support of the ITER blanket fabrication, this study clarified the neutron irradiation effect on the tensile properties of HIP joints using stainless steels and the effect of surface roughness (Ry) at the joint boundary on tensile properties of HIP joints. Three different types of joints (type-A: Ry = 1 m, type-B: Ry = 10 m and type-C: Ry = 30 m) were prepared and irradiated up to 1.5 dpa at 240–250 ◦ C. It was determined that the tensile properties of HIP joints were almost the same as those of stainless-steel base material irrespective of neutron irradiation. The difference in surface roughness condition and total elongation of irradiated type-C joints was smaller than that of the other types of joints, but the tensile strength of HIP joints was not changed by the surface roughness condition. This study confirmed that the tensile strength of HIP joints by the standard HIP condition was almost the same as that of the base material after neutron irradiation, and that it is possible to alleviate the requirement on surface roughness condition for HIP joining as part of the ITER blanket fabrication. © 2005 Elsevier B.V. All rights reserved. Keywords: HIP joint; Neutron irradiation effect; Joint boundary condition; ITER shielding blanket
1. Introduction In the International Thermonuclear Experimental Reactor (ITER), dispersion strengthened copper ∗ Corresponding author. Tel.: +81 29 266 7369; fax: +81 29 266 7481. E-mail address: [email protected] (H. Yamada).
0920-3796/$ – see front matter © 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.fusengdes.2005.07.012
(DSCu) has been selected as a candidate material for the first wall of the blanket due to its high strength and high thermal conductivity at high temperature [1]. Stainless steel such as SS316LN-IG is a candidate structural material for the body of the ITER blanket [2]. During the fabrication of the ITER blanket, SS316LN-IG and DSCu are joined to form the first wall, and SS316LN-IG and SS316LN-IG are joined to
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form the body by a hot isostatic pressing (HIP) joint method. The HIP joint method is a kind of diffusion joint. It is used as a joint method for different materials or as a fabrication method of complex curved structures. The performance of the joint depends strongly on HIP conditions, as shown by several studies on optimization of the joining procedure using un-irradiated DSCu and SS316LN-IG [1–3] and by other studies reporting mechanical properties of irradiated HIP joints [4,5]. Mechanical properties of HIP joints using DSCu and SS316LN-IG have been investigated using unirradiated materials and irradiated materials [6,7]. On the other hand, there are few studies of SS316LN-IG and SS316LN-IG HIP joints (SS/SS HIP joints) for the fabrication of the ITER shielding blanket. The HIP joint temperature for fabrication of the ITER shielding blanket is limited mainly by the melting point of DSCu (1083 ◦ C). The standard HIP temperature for the ITER shielding blanket fabrication method proposed by the Japanese team of ITER is 1050 ◦ C and the impact of this temperature condition on irradiated SS/SS HIP joint material has not been verified. In this study, mechanical properties of irradiated SS/SS HIP joints are examined, and the effect of the HIP joint condition on mechanical properties of irradiated HIP joints was investigated.
2. Material and specimen SS316LN-IG is a candidate structural material for the shielding blanket of ITER [8] and was used as structural material for the joint manufacturing in this study. The SS316LN-IG was fabricated by Japan Steel Works Ltd.; its chemical composition is shown in Table 1.
Table 1 Chemical composition (wt.%) of SS316LN-IG Fe C Mn Si P S Cr Ni Mo Nb Cu Co N B
Balance 0.029 1.64 0.44 0.012 0.009 17.48 12.11 2.56 0.067 0.02 0.02 0.067 0.0003
The HIP joints were fabricated by Kawasaki Heavy Industries Ltd. The joining parameters used in this study were based upon the recommended condition from the blanket fabrication by the Japanese team of ITER, which were optimized in an earlier study on unirradiated materials [6]. To help assess the effect of the HIP joint condition, two different HIP joint pressures and three different surface roughness (Ry) on the surface of the joined material were used, as shown in Table 2. The dimensions of the tensile specimens are shown in Fig. 1. Additionally, tensile specimens of SS316LNIG base material with the thermal history on HIP joint procedure were prepared as reference HIP joints.
3. Irradiation test These specimens were set into an irradiation capsule filled with helium, and were irradiated for four operation cycles (corresponding to about
Table 2 HIP joint conditions of joints specimen Name of joints
Pressure (MPa)
Temperature (◦ C)
Surface roughness of joint boundary, Ry (m)
Standard HIP joints Type-A joints Type-B joints Type-C joints
150 200 200 200
1050 1050 1050 1050
<1 <1 <10 <30
Hold time of all joint condition is 2 h.
H. Yamada et al. / Fusion Engineering and Design 81 (2006) 631–637
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specimens was recorded by iron fluence monitors, and the maximum value was evaluated as 1.2 × 1025 n/m−2 (E >1 MeV). The displacement dose of the specimens was calculated as 2.1 displacements per atom (dpa). The thermal neutron fluence was recorded using Al–Co monitors and the maximum value was evaluated as 2.5 × 1025 n/m−2 (E < 0.68 eV). The irradiation temperature of the specimens was estimated by the ABAQUS code [9] to be between 240 and 250 ◦ C along the length of the specimens.
4. Post-irradiation examinations
Fig. 1. Dimension of HIP joints specimen. (1) SS316LNIG/SS316LN-IG HIP joints; (2) SS316LN-IG base material.
100 days) at the Japan Materials Testing Reactor (JMTR), which is located in the Oarai Research Establishment of Japan Atomic Energy Research Institute (JAERI). The fast neutron fluence of the
For evaluation of the mechanical properties of the various HIP joints, tensile tests were performed at 25 and 250 ◦ C in air. A crosshead speed controlled at 0.1 mm/min (which corresponds to a strain rate of about 0.33%/min) was used before the 0.2% yield stress (0.2%YS) was reached, and then the strain rate was changed to 1.0 mm/min (about 3.3%/min).
Fig. 2. Tensile properties of SS/SS HIP joints and SS316LN-IG base material.
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Fig. 3. Fracture position of SS/SS HIP joints and SS316LN-IG base material after tensile test.
Fig. 4. The effect of HIP pressure on tensile properties.
H. Yamada et al. / Fusion Engineering and Design 81 (2006) 631–637
5. Results and discussion 5.1. Neutron irradiation effect Results of tensile tests are shown in Fig. 2 for the SS316LN-IG/SS316LN-IG HIP joints fabricated by the standard HIP joint condition proposed by the Japanese team of the ITER project, together with results for the SS316LN-IG base material. The standard HIP joint condition of the Japanese team of the ITER project is shown in Table 2. These results show that tensile properties of the HIP joints were almost the same as those of the SS316LNIG base material and this trend did not change after neutron irradiation.
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Fracture positions of the HIP joints and the base material are shown in Fig. 3. Fracture position and fracture surface of all specimens were almost the same, irrespective of neutron irradiation. Thus, it was verified that the tensile properties of the SS/SS HIP joints, which have been made by the standard HIP condition, were almost the same as those of the SS316LN-IG base material. 5.2. The effect of HIP joint pressure To help assess the effect of HIP joint pressure on the joint properties, the tensile properties of HIP joints which have been made at a HIP pressure of 150 MPa were compared with those of HIP joints which have
Fig. 5. The effect of surface roughness condition of HIP joint boundary on tensile properties.
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been made at a HIP pressure of 200 MPa. Results of these tensile tests for HIP joints are shown in Fig. 4, together with results for the SS316LN-IG base material. These results show that the ultimate tensile strength (UTS) of HIP joints with 150 MPa HIP pressure was almost the same as that of HIP joints with 200 MPa HIP pressure (both with and without neutron irradiation). On the other hand, the total elongation (TEL) of HIP joints with 200 MPa HIP pressure was larger than that of HIP joints with 150 MPa HIP pressure for unirradiated material. Generally, defects or micro-voids in material are removed when the material is kept at high temperature and high pressure. This effect would be applied to remove defects from casting material. In this case, it is considered that the impact of defects in the material would be decreased by the HIP pressure. However, TEL of HIP joint with HIP pressure of 150 MPa was almost the same as that of HIP joints with HIP pressure of 200 MPa for neutron-irradiated material. It is considered that the effect of irradiation defect was larger than the effect of material fabrication defect on the elongation property of HIP joints. Therefore, it is considered that an un-irradiated HIP joint would be improved by high HIP pressure condition. However, there is no effect of HIP pressure between 150 and 200 MPa on the HIP joints for fabrication of the ITER blanket. 5.3. The effect of the HIP boundary condition Results of tensile tests are shown in Fig. 5 for HIP joints made by three types of HIP joint conditions and also for the SS316LN-IG base material. For unirradiated materials, the UTS and TEL of SS/SS HIP joints did not change for the different surface roughnesses used at the HIP joint boundary. From these results, it is considered that tensile properties of unirradiated SS/SS HIP joints do not depend on the surface roughness (in the range 1–30 m). The UTS of irradiated SS/SS HIP joints was not changed by the surface roughness condition, but the TEL of irradiated type-C joints was a little lower than that of the other types of joints. For consideration of this cause, the fracture positions of the three irradiated types HIP joints are shown in Fig. 6. Specimens of
Fig. 6. Fracture position of three types SS/SS HIP joints after tensile test. (a) Type-A HIP joints specimens after tensile test; (b) type-B HIP joints specimens after tensile test; (c) type-C HIP joints specimens after tensile test.
the type-A HIP joints (Ry = 1 m) and specimens of the type-B HIP joints (Ry = 10 m) were fractured at the base material, but specimens of the type-C HIP joints (Ry = 30 m) were fractured at the center of the specimen where the joint boundary position is located. Generally, diffusion to grain boundary is more easy than that into the inside of grain. It is considered that elements diffuse to grain boundary rather than into the inside of grain on the type-C HIP joints and the factor for detachment of grain boundary were generated by the diffusion at grain boundary. This could explain the TEL of type-C HIP joints being lower than that of the other types of HIP joints. However, the tensile strengths of all types of HIP joints were almost the same for irradiated and unirradiated materials. Therefore, it is considered that the surface roughness condition of 30 m can be applied for HIP joints condition for the SS/SS HIP joints in ITER blanket fabrication.
H. Yamada et al. / Fusion Engineering and Design 81 (2006) 631–637
6. Conclusion This study clarified the following points: (1) The standard HIP joint condition recommended by the Japanese team of the ITER project (i.e., HIP pressure: 150 MPa, HIP temperature: 1050 ◦ C, hold time: 2 h, surface roughness: Ry < 1 m) can also be applied to the HIP joint condition for irradiated SS/SS HIP joints. (2) The tensile strengths of SS/SS HIP joints do not depend on the surface roughness condition between 1 to 30 m at the HIP joint boundary, irrespective of neutron irradiation. Thus, this study has confirmed that tensile properties of HIP joints by the standard HIP condition proposed by the Japanese team of ITER was almost the same as that of the irradiated SS316LN-IG base material and the possibility of alleviation of surface roughness condition for HIP joint boundary for ITER blanket fabrication was shown.
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References [1] R. Aymar, J. Nucl. Mater. 258–263 (1998) 56–64. [2] A.A.F. Tavassoli, J. Nucl. Mater. 258–263 (1998) 85– 96. [3] A.S. Pokrovsky, S.A. Fabritsiev, D.J. Edwards, S.J. Zinkle, J. Nucl. Mater. 283–287 (2000) 404–408. [4] A. Lind, U. Bergenlid, J. Nucl. Mater. 283–287 (2000) 451– 454. [5] S.A. Fabritsiev, A.S. Pokrovsky, D.J. Edwards, S.J. Zinkle, J. Nucl. Mater. 283–287 (2000) 523–527. [6] S. Sato, T. Hatano, T. Kuroda, K. Furuya, S. Hara, M. Enoeda, H. Takatsu, J. Nucl. Mater. 258–263 (1998) 265– 270. [7] H. Yamada, H. Kawamura, K. Tsuchiya, G. Kalinin, Y. Nagao, S. Sato, K. Mohri, J. Nucl. Mater. 335 (2004) 33–38. [8] F. Elio, K. Ioki, P. Barabaschi, L. Bruno, A. Cardella, M. Hechler, T. Kodama, A. Lodato, D. Loesser, D. Lousteau, N. Miki, K. Mohri, R. Parker, R. Raffray, D. Williamson, M. Yamada, W. Daenner, R. Mattas, Y. Strebkov, H. Takatsu, Fusion Eng. 46 (1999) 159–175. [9] Hibbitt, Karlsson & Sorensen, Inc., ABAQUS/Standard User’s Manual, Version 5.7, Hibbitt, Karlsson & Sorensen, Inc., 1997.
Neutron irradiation effect on mechanical properties of SS/SS hip joint materials for ITER shielding blankets Hirokazu Yamada a,∗ , Satoshi Sato b , Kensuke Mohri b , Yoshiharu Nagao a , Fumiki Takada a , Hiroshi Kawamura b a
b
Japan Atomic Energy Agency (JAEA), 3607 Narita-Cho, Oarai-machi, Higashiibaraki-gun, Ibaraki-ken 311-1394, Japan Japan Atomic Energy Agency (JAEA), Naka-shi, lbaraki-ken 311-0193, Japan
Received 31 January 2005; received in revised form 21 July 2005; accepted 21 July 2005 Available online 20 December 2005
Abstract In support of the ITER blanket fabrication, this study clarified the neutron irradiation effect on the tensile properties of HIP joints using stainless steels and the effect of surface roughness (Ry) at the joint boundary on tensile properties of HIP joints. Three different types of joints (type-A: Ry = 1 m, type-B: Ry = 10 m and type-C: Ry = 30 m) were prepared and irradiated up to 1.5 dpa at 240–250 ◦ C. It was determined that the tensile properties of HIP joints were almost the same as those of stainless-steel base material irrespective of neutron irradiation. The difference in surface roughness condition and total elongation of irradiated type-C joints was smaller than that of the other types of joints, but the tensile strength of HIP joints was not changed by the surface roughness condition. This study confirmed that the tensile strength of HIP joints by the standard HIP condition was almost the same as that of the base material after neutron irradiation, and that it is possible to alleviate the requirement on surface roughness condition for HIP joining as part of the ITER blanket fabrication. © 2005 Elsevier B.V. All rights reserved. Keywords: HIP joint; Neutron irradiation effect; Joint boundary condition; ITER shielding blanket
1. Introduction In the International Thermonuclear Experimental Reactor (ITER), dispersion strengthened copper ∗ Corresponding author. Tel.: +81 29 266 7369; fax: +81 29 266 7481. E-mail address: [email protected] (H. Yamada).
0920-3796/$ – see front matter © 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.fusengdes.2005.07.012
(DSCu) has been selected as a candidate material for the first wall of the blanket due to its high strength and high thermal conductivity at high temperature [1]. Stainless steel such as SS316LN-IG is a candidate structural material for the body of the ITER blanket [2]. During the fabrication of the ITER blanket, SS316LN-IG and DSCu are joined to form the first wall, and SS316LN-IG and SS316LN-IG are joined to
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H. Yamada et al. / Fusion Engineering and Design 81 (2006) 631–637
form the body by a hot isostatic pressing (HIP) joint method. The HIP joint method is a kind of diffusion joint. It is used as a joint method for different materials or as a fabrication method of complex curved structures. The performance of the joint depends strongly on HIP conditions, as shown by several studies on optimization of the joining procedure using un-irradiated DSCu and SS316LN-IG [1–3] and by other studies reporting mechanical properties of irradiated HIP joints [4,5]. Mechanical properties of HIP joints using DSCu and SS316LN-IG have been investigated using unirradiated materials and irradiated materials [6,7]. On the other hand, there are few studies of SS316LN-IG and SS316LN-IG HIP joints (SS/SS HIP joints) for the fabrication of the ITER shielding blanket. The HIP joint temperature for fabrication of the ITER shielding blanket is limited mainly by the melting point of DSCu (1083 ◦ C). The standard HIP temperature for the ITER shielding blanket fabrication method proposed by the Japanese team of ITER is 1050 ◦ C and the impact of this temperature condition on irradiated SS/SS HIP joint material has not been verified. In this study, mechanical properties of irradiated SS/SS HIP joints are examined, and the effect of the HIP joint condition on mechanical properties of irradiated HIP joints was investigated.
2. Material and specimen SS316LN-IG is a candidate structural material for the shielding blanket of ITER [8] and was used as structural material for the joint manufacturing in this study. The SS316LN-IG was fabricated by Japan Steel Works Ltd.; its chemical composition is shown in Table 1.
Table 1 Chemical composition (wt.%) of SS316LN-IG Fe C Mn Si P S Cr Ni Mo Nb Cu Co N B
Balance 0.029 1.64 0.44 0.012 0.009 17.48 12.11 2.56 0.067 0.02 0.02 0.067 0.0003
The HIP joints were fabricated by Kawasaki Heavy Industries Ltd. The joining parameters used in this study were based upon the recommended condition from the blanket fabrication by the Japanese team of ITER, which were optimized in an earlier study on unirradiated materials [6]. To help assess the effect of the HIP joint condition, two different HIP joint pressures and three different surface roughness (Ry) on the surface of the joined material were used, as shown in Table 2. The dimensions of the tensile specimens are shown in Fig. 1. Additionally, tensile specimens of SS316LNIG base material with the thermal history on HIP joint procedure were prepared as reference HIP joints.
3. Irradiation test These specimens were set into an irradiation capsule filled with helium, and were irradiated for four operation cycles (corresponding to about
Table 2 HIP joint conditions of joints specimen Name of joints
Pressure (MPa)
Temperature (◦ C)
Surface roughness of joint boundary, Ry (m)
Standard HIP joints Type-A joints Type-B joints Type-C joints
150 200 200 200
1050 1050 1050 1050
<1 <1 <10 <30
Hold time of all joint condition is 2 h.
H. Yamada et al. / Fusion Engineering and Design 81 (2006) 631–637
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specimens was recorded by iron fluence monitors, and the maximum value was evaluated as 1.2 × 1025 n/m−2 (E >1 MeV). The displacement dose of the specimens was calculated as 2.1 displacements per atom (dpa). The thermal neutron fluence was recorded using Al–Co monitors and the maximum value was evaluated as 2.5 × 1025 n/m−2 (E < 0.68 eV). The irradiation temperature of the specimens was estimated by the ABAQUS code [9] to be between 240 and 250 ◦ C along the length of the specimens.
4. Post-irradiation examinations
Fig. 1. Dimension of HIP joints specimen. (1) SS316LNIG/SS316LN-IG HIP joints; (2) SS316LN-IG base material.
100 days) at the Japan Materials Testing Reactor (JMTR), which is located in the Oarai Research Establishment of Japan Atomic Energy Research Institute (JAERI). The fast neutron fluence of the
For evaluation of the mechanical properties of the various HIP joints, tensile tests were performed at 25 and 250 ◦ C in air. A crosshead speed controlled at 0.1 mm/min (which corresponds to a strain rate of about 0.33%/min) was used before the 0.2% yield stress (0.2%YS) was reached, and then the strain rate was changed to 1.0 mm/min (about 3.3%/min).
Fig. 2. Tensile properties of SS/SS HIP joints and SS316LN-IG base material.
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Fig. 3. Fracture position of SS/SS HIP joints and SS316LN-IG base material after tensile test.
Fig. 4. The effect of HIP pressure on tensile properties.
H. Yamada et al. / Fusion Engineering and Design 81 (2006) 631–637
5. Results and discussion 5.1. Neutron irradiation effect Results of tensile tests are shown in Fig. 2 for the SS316LN-IG/SS316LN-IG HIP joints fabricated by the standard HIP joint condition proposed by the Japanese team of the ITER project, together with results for the SS316LN-IG base material. The standard HIP joint condition of the Japanese team of the ITER project is shown in Table 2. These results show that tensile properties of the HIP joints were almost the same as those of the SS316LNIG base material and this trend did not change after neutron irradiation.
635
Fracture positions of the HIP joints and the base material are shown in Fig. 3. Fracture position and fracture surface of all specimens were almost the same, irrespective of neutron irradiation. Thus, it was verified that the tensile properties of the SS/SS HIP joints, which have been made by the standard HIP condition, were almost the same as those of the SS316LN-IG base material. 5.2. The effect of HIP joint pressure To help assess the effect of HIP joint pressure on the joint properties, the tensile properties of HIP joints which have been made at a HIP pressure of 150 MPa were compared with those of HIP joints which have
Fig. 5. The effect of surface roughness condition of HIP joint boundary on tensile properties.
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been made at a HIP pressure of 200 MPa. Results of these tensile tests for HIP joints are shown in Fig. 4, together with results for the SS316LN-IG base material. These results show that the ultimate tensile strength (UTS) of HIP joints with 150 MPa HIP pressure was almost the same as that of HIP joints with 200 MPa HIP pressure (both with and without neutron irradiation). On the other hand, the total elongation (TEL) of HIP joints with 200 MPa HIP pressure was larger than that of HIP joints with 150 MPa HIP pressure for unirradiated material. Generally, defects or micro-voids in material are removed when the material is kept at high temperature and high pressure. This effect would be applied to remove defects from casting material. In this case, it is considered that the impact of defects in the material would be decreased by the HIP pressure. However, TEL of HIP joint with HIP pressure of 150 MPa was almost the same as that of HIP joints with HIP pressure of 200 MPa for neutron-irradiated material. It is considered that the effect of irradiation defect was larger than the effect of material fabrication defect on the elongation property of HIP joints. Therefore, it is considered that an un-irradiated HIP joint would be improved by high HIP pressure condition. However, there is no effect of HIP pressure between 150 and 200 MPa on the HIP joints for fabrication of the ITER blanket. 5.3. The effect of the HIP boundary condition Results of tensile tests are shown in Fig. 5 for HIP joints made by three types of HIP joint conditions and also for the SS316LN-IG base material. For unirradiated materials, the UTS and TEL of SS/SS HIP joints did not change for the different surface roughnesses used at the HIP joint boundary. From these results, it is considered that tensile properties of unirradiated SS/SS HIP joints do not depend on the surface roughness (in the range 1–30 m). The UTS of irradiated SS/SS HIP joints was not changed by the surface roughness condition, but the TEL of irradiated type-C joints was a little lower than that of the other types of joints. For consideration of this cause, the fracture positions of the three irradiated types HIP joints are shown in Fig. 6. Specimens of
Fig. 6. Fracture position of three types SS/SS HIP joints after tensile test. (a) Type-A HIP joints specimens after tensile test; (b) type-B HIP joints specimens after tensile test; (c) type-C HIP joints specimens after tensile test.
the type-A HIP joints (Ry = 1 m) and specimens of the type-B HIP joints (Ry = 10 m) were fractured at the base material, but specimens of the type-C HIP joints (Ry = 30 m) were fractured at the center of the specimen where the joint boundary position is located. Generally, diffusion to grain boundary is more easy than that into the inside of grain. It is considered that elements diffuse to grain boundary rather than into the inside of grain on the type-C HIP joints and the factor for detachment of grain boundary were generated by the diffusion at grain boundary. This could explain the TEL of type-C HIP joints being lower than that of the other types of HIP joints. However, the tensile strengths of all types of HIP joints were almost the same for irradiated and unirradiated materials. Therefore, it is considered that the surface roughness condition of 30 m can be applied for HIP joints condition for the SS/SS HIP joints in ITER blanket fabrication.
H. Yamada et al. / Fusion Engineering and Design 81 (2006) 631–637
6. Conclusion This study clarified the following points: (1) The standard HIP joint condition recommended by the Japanese team of the ITER project (i.e., HIP pressure: 150 MPa, HIP temperature: 1050 ◦ C, hold time: 2 h, surface roughness: Ry < 1 m) can also be applied to the HIP joint condition for irradiated SS/SS HIP joints. (2) The tensile strengths of SS/SS HIP joints do not depend on the surface roughness condition between 1 to 30 m at the HIP joint boundary, irrespective of neutron irradiation. Thus, this study has confirmed that tensile properties of HIP joints by the standard HIP condition proposed by the Japanese team of ITER was almost the same as that of the irradiated SS316LN-IG base material and the possibility of alleviation of surface roughness condition for HIP joint boundary for ITER blanket fabrication was shown.
637
References [1] R. Aymar, J. Nucl. Mater. 258–263 (1998) 56–64. [2] A.A.F. Tavassoli, J. Nucl. Mater. 258–263 (1998) 85– 96. [3] A.S. Pokrovsky, S.A. Fabritsiev, D.J. Edwards, S.J. Zinkle, J. Nucl. Mater. 283–287 (2000) 404–408. [4] A. Lind, U. Bergenlid, J. Nucl. Mater. 283–287 (2000) 451– 454. [5] S.A. Fabritsiev, A.S. Pokrovsky, D.J. Edwards, S.J. Zinkle, J. Nucl. Mater. 283–287 (2000) 523–527. [6] S. Sato, T. Hatano, T. Kuroda, K. Furuya, S. Hara, M. Enoeda, H. Takatsu, J. Nucl. Mater. 258–263 (1998) 265– 270. [7] H. Yamada, H. Kawamura, K. Tsuchiya, G. Kalinin, Y. Nagao, S. Sato, K. Mohri, J. Nucl. Mater. 335 (2004) 33–38. [8] F. Elio, K. Ioki, P. Barabaschi, L. Bruno, A. Cardella, M. Hechler, T. Kodama, A. Lodato, D. Loesser, D. Lousteau, N. Miki, K. Mohri, R. Parker, R. Raffray, D. Williamson, M. Yamada, W. Daenner, R. Mattas, Y. Strebkov, H. Takatsu, Fusion Eng. 46 (1999) 159–175. [9] Hibbitt, Karlsson & Sorensen, Inc., ABAQUS/Standard User’s Manual, Version 5.7, Hibbitt, Karlsson & Sorensen, Inc., 1997.