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Li, Y.; Hirota, Takatoshi*; Itabashi, Yu*; Yamamoto, Masato*; Kanto, Yasuhiro*; Suzuki, Masahide*; Miyamoto, Yuhei*
JAEA-Review 2020-011, 130 Pages, 2020/09
JAEA-Review-2020-011.pdf:9.31MB
For the improvement of the structural integrity assessment methodology on reactor pressure vessels (RPVs), the probabilistic fracture mechanics (PFM) analysis code PASCAL has been developed and improved in Japan Atomic Energy Agency based on the latest knowledge. The PASCAL code evaluates the failure probabilities and frequencies of Japanese RPVs under transient events such as pressure thermal shock considering neutron irradiation embrittlement. In order to confirm the reliability of the PASCAL as a domestic standard code and to promote the application of PFM on the domestic structural integrity assessments of RPVs, it is important to perform verification activities, and summarize the verification processes and results as a document. On the basis of these backgrounds, we established a working group, composed of experts on this field besides the developers, on the verification of the PASCAL module and the source program of PASCAL was released to the members of working group. This report summarizes the activities of the working group on the verification of PASCAL in FY2016 and FY2017.
Yamamoto, Masato*; Onizawa, Kunio; Yoshimoto, Kentaro*; Ogawa, Takuya*; Mabuchi, Yasuhiro*; Valo, M.*; Lambrecht, M.*; Viehrig, H.-W.*; Miura, Naoki*; Soneda, Naoki*
Small Specimen Test Techniques; 6th Volume (ASTM STP 1576), p.53 - 69, 2015/05
In order to ensure the robustness of the Master Curve technique, round-robin tests were performed using 0.16 inch-thick Mini-CT specimens by different investigators to see if consistent 
values can be obtained. All the specimens used were machined and pre-cracked by one fabricator from unique Japanese RPV material. Seven institutes participated in this exercise, and obtained valid values according to the ASTM E1921 standard. The scatter of values obtained was well within the uncertainty range defined in the standard, indicating the robustness of the Mini-CT specimen test technique. Throughout this activity, we could obtain 182 
for a single material. We investigated the statistics of this large database, and found that there is no remarkable difference not only in the values but also in the fracture toughness distribution between the Mini-CT specimen and the standard size 1T-C(T) specimen results.
under various selections of temperature conditionsYamamoto, Masato*; Kimura, Akihiko*; Onizawa, Kunio; Yoshimoto, Kentaro*; Ogawa, Takuya*; Mabuchi, Yasuhiro*; Viehrig, H.-W.*; Miura, Naoki*; Soneda, Naoki*
Proceedings of 2014 ASME Pressure Vessels and Piping Conference (PVP 2014) (DVD-ROM), 7 Pages, 2014/07
The Master Curve (MC) approach for the fracture toughness reference temperature To is expected to be a powerful tool to ensure the reliability of long-term used RPV steels. In order to get sufficient number of data for the MC approach related to the present surveillance program for RPVs, the use of miniature specimens is important. The test technique for the miniature specimens (Mini-CT) of 4 mm thick had been verified the basic applicability of MC approach by means of Mini-CT for the determination of fracture toughness of typical Japanese RPV steels. A round robin (RR) program was organized to assure the robustness of the technique. As the third step of RR program, blinded tests were carried out. Precise material information was not provided to the participants. From the results obtained, the scatter range in was within the acceptable scatter range specified in the testing standard. The selection of testing temperature seems to give limited effect like that in larger specimens.
Nishimori, Nobuyuki; Nagai, Ryoji; Matsuba, Shunya; Hajima, Ryoichi; Yamamoto, Masahiro*; Miyajima, Tsukasa*; Honda, Yosuke*; Uchiyama, Takashi*; Iijima, Hokuto*; Kuriki, Masao*; et al.
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.174 - 178, 2014/06
no abstracts in English
500 kVNishimori, Nobuyuki; Nagai, Ryoji; Matsuba, Shunya; Hajima, Ryoichi; Yamamoto, Masahiro*; Honda, Yosuke*; Miyajima, Tsukasa*; Iijima, Hokuto*; Kuriki, Masao*; Kuwahara, Makoto*
Physical Review Special Topics; Accelerators and Beams, 17(5), p.053401_1 - 053401_17, 2014/05
Times Cited Count：23 Percentile：80.23(Physics, Nuclear)Nishimori, Nobuyuki; Nagai, Ryoji; Matsuba, Shunya; Hajima, Ryoichi; Yamamoto, Masahiro*; Honda, Yosuke*; Miyajima, Tsukasa*; Iijima, Hokuto*; Kuriki, Masao*; Kuwahara, Makoto*
Proceedings of 35th International Free-Electron Laser Conference (FEL 2013) (Internet), p.184 - 188, 2013/08
Nishimori, Nobuyuki; Nagai, Ryoji; Matsuba, Shunya; Hajima, Ryoichi; Yamamoto, Masahiro*; Miyajima, Tsukasa*; Honda, Yosuke*; Iijima, Hokuto*; Kuriki, Masao*; Kuwahara, Makoto*; et al.
Proceedings of 9th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.255 - 259, 2013/08
no abstracts in English
Yamamoto, Masato*; Onizawa, Kunio; Yoshimoto, Kentaro*; Ogawa, Takuya*; Mabuchi, Yasuhiro*; Miura, Naoki*
Proceedings of 2013 ASME Pressure Vessels and Piping Conference (PVP 2013) (DVD-ROM), 8 Pages, 2013/07
Master Curve (MC) approach for the fracture toughness evaluation is expected to be a powerful tool to assess the structural integrity of reactor pressure vessels (RPVs). In order to get sufficient number of reliable data by the MC approach from used specimens of surveillance tests for RPVs, the use of miniature specimens is necessary. For this purpose, a round robin test program on the miniature compact tension specimens (Mini-CT) of 4 mm thick for the MC approach was launched with the participation of academia, industries and a research institute in Japan. The program aims to verify the reliability of experimental data from Mini-CT, and to pick out technical issues to be solved. As the second step of this program, the effect of loading rate (d/d
) was evaluated based on enlarged database. Despite of the difference in d/d, no specific difference in scatter band of 
was found in d/d - relationships. D/d seems not to be sensitive on scatter band of To in the present results.
Nishimori, Nobuyuki; Nagai, Ryoji; Matsuba, Shunya; Hajima, Ryoichi; Yamamoto, Masahiro*; Miyajima, Tsukasa*; Honda, Yosuke*; Iijima, Hokuto*; Kuriki, Masao*; Kuwahara, Makoto*
Applied Physics Letters, 102(23), p.234103_1 - 234103_4, 2013/06
Times Cited Count：20 Percentile：63.34(Physics, Applied)Nishimori, Nobuyuki; Nagai, Ryoji; Matsuba, Shunya; Hajima, Ryoichi; Yamamoto, Masahiro*; Honda, Yosuke*; Miyajima, Tsukasa*; Iijima, Hokuto*; Kuriki, Masao*; Kuwahara, Makoto*
Proceedings of 4th International Particle Accelerator Conference (IPAC '13) (Internet), p.321 - 323, 2013/05
Nishimori, Nobuyuki; Nagai, Ryoji; Matsuba, Shunya; Hajima, Ryoichi; Yamamoto, Masahiro*; Honda, Yosuke*; Miyajima, Tsukasa*; Iijima, Hokuto*; Kuriki, Masao*; Kuwahara, Makoto*; et al.
Proceedings of 34th International Free Electron Laser Conference (FEL 2012) (Internet), p.161 - 164, 2012/08
Yamamoto, Masato*; Kimura, Akihiko*; Onizawa, Kunio; Yoshimoto, Kentaro*; Ogawa, Takuya*; Chiba, Atsushi*; Hirano, Takashi*; Sugihara, Takuji*; Sugiyama, Masanari*; Miura, Naoki*; et al.
Proceedings of 2012 ASME Pressure Vessels and Piping Conference (PVP 2012) (DVD-ROM), 7 Pages, 2012/07
Master curve (MC) approach for the fracture toughness evaluation is expected to be a powerful tool to assess the structural integrity of reactor pressure vessels (RPVs). In order to get sufficient number of reliable data for the MC approach from broken halves of surveillance test specimens for RPVs, the use of miniature specimens is necessary. For this purpose, a round robin test program on the miniature compact tension specimens (Mini-CT) of 4 mm thick for the MC approach of a Japanese RPV steel has been launched with the participation of academia, industries and a research institute in Japan. The program aims to verify the reliability of experimental data from Mini-CT, and to pick out further investigation items to be solved. As the first step of this program, four institutes carried out MC testing and evaluation using common test procedure and specimens. Valid reference temperature T was successfully obtained in each institute. However, the T values showed large differences with maximum of 34
C. It was indicated on the reason of difference that there is a strong correlation between the T values and loading rate, which was selected by each institute per test standard.
Nishimori, Nobuyuki; Nagai, Ryoji; Hajima, Ryoichi; Yamamoto, Masahiro*; Miyajima, Tsukasa*; Honda, Yosuke*; Iijima, Hokuto*; Kuriki, Masao*; Kuwahara, Makoto*; Okumi, Shoji*; et al.
Proceedings of 8th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.20 - 23, 2011/08
no abstracts in English
Nishimori, Nobuyuki; Nagai, Ryoji; Yamamoto, Masahiro*; Honda, Yosuke*; Miyajima, Tsukasa*; Iijima, Hokuto*; Kuriki, Masao*; Kuwahara, Makoto*; Okumi, Shoji*; Nakanishi, Tsutomu*; et al.
Journal of Physics; Conference Series, 298, p.012005_1 - 012005_6, 2011/06
Nishimori, Nobuyuki; Nagai, Ryoji; Hajima, Ryoichi; Yamamoto, Masahiro*; Honda, Yosuke*; Miyajima, Tsukasa*; Muto, Toshiya*; Iijima, Hokuto*; Kuriki, Masao*; Kuwahara, Makoto*; et al.
Proceedings of 25th International Linear Accelerator Conference (LINAC 2010) (CD-ROM), p.995 - 997, 2010/09
Nagai, Ryoji; Nishimori, Nobuyuki; Hajima, Ryoichi; Muto, Toshiya*; Yamamoto, Masahiro*; Miyajima, Tsukasa*; Honda, Yosuke*; Iijima, Hokuto*; Kuriki, Masao*; Kuwahara, Makoto*; et al.
Proceedings of 7th Annual Meeting of Particle Accelerator Society of Japan (DVD-ROM), p.806 - 808, 2010/08
A 500-kV, 10-mA photocathode DC gun which is designed for next-generation light- sources based on energy-recovery linac has been developed in a collaboration effort of JAEA, KEK, Hiroshima University and Nagoya University. We have utilized a segmented cylindrical ceramic insulator and guard-ring electrodes to prevent any damage to the insulator from electrons emitted by the support-rod electrode. The 500-kV gun was successfully conditioned up to a voltage of 550 kV and a long-time holding test for 8 h was demonstrated at an acceleration voltage of 500 kV. The cathode electrode, anode electrode, and beam line apparatuses are now under fabrication and beam tests of the gun will be started soon.
Nishimori, Nobuyuki; Nagai, Ryoji; Hajima, Ryoichi; Yamamoto, Masahiro*; Miyajima, Tsukasa*; Honda, Yosuke*; Muto, Toshiya*; Iijima, Hokuto*; Kuriki, Masao*; Kuwahara, Makoto*; et al.
Proceedings of 7th Annual Meeting of Particle Accelerator Society of Japan (DVD-ROM), p.802 - 805, 2010/08
no abstracts in English
Yamamoto, Masahiro*; Uchiyama, Takashi*; Miyajima, Tsukasa*; Honda, Yosuke*; Sato, Kotaro*; Matsuba, Shunya*; Saito, Yoshio*; Kobayashi, Masanori*; Kurisu, Hiriki*; Hajima, Ryoichi; et al.
Proceedings of 7th Annual Meeting of Particle Accelerator Society of Japan (DVD-ROM), p.717 - 720, 2010/08
A 500-kV photocathode DC electron gun which can supply the beam of a low emittance and a high average current has been developed in collaboration with KEK, JAEA, Hiroshima Univ., Nagoya Univ. and Yamaguchi Univ. The vacuum of the gun chamber has to be lower Extreme High Vacuum for maintain cathode-life time. A titanium chamber and new material of ceramic were employed to reduce outgassing rate. The result of outgassing rate of the gun chamber is described in this report.
Nagai, Ryoji; Hajima, Ryoichi; Nishimori, Nobuyuki; Muto, Toshiya*; Yamamoto, Masahiro*; Honda, Yosuke*; Miyajima, Tsukasa*; Kuriki, Masao*; Iijima, Hokuto*; Kuwahara, Makoto*; et al.
Kasokuki, 7(2), p.88 - 94, 2010/07
A 500-kV, 10-mA photocathode DC gun which is designed for next-generation light-sources based on energy-recovery linac has been developed in a collaboration effort of JAEA, KEK, Hiroshima University and Nagoya University. We have utilized a segmented cylindrical ceramic insulator and guard-ring electrodes to prevent any damage to the insulator from electrons emitted by the support-rod electrode. The 500-kV gun was successfully conditioned up to a voltage of 550 kV and a long-time holding test for 8 h was demonstrated at an acceleration voltage of 500 kV. The 500-kV gun consists of a Cockcroft-Walton generator, a segmented cylindrical ceramic insulator, guard-ring electrodes, a support-rod electrode, a vacuum chamber, and a pressurized insulating gas tank. The cathode electrode, anode electrode, and beam line apparatuses are now under fabrication and beam tests of the gun will be started soon.
Nagai, Ryoji; Hajima, Ryoichi; Nishimori, Nobuyuki; Muto, Toshiya*; Yamamoto, Masahiro*; Honda, Yosuke*; Miyajima, Tsukasa*; Kuriki, Masao*; Iijima, Hokuto*; Kuwahara, Makoto*; et al.
Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.2341 - 2343, 2010/05
A 500-kV, 10-mA photocathode DC gun has been developed in a collaboration effort of JAEA, KEK, Hiroshima University and Nagoya University. We have utilized a segmented cylindrical ceramic insulator and guard-ring electrodes to prevent any damage to the insulator from electrons emitted by the support-rod electrode. The high-voltage test of the gun has been successfully done with up to 550 kV. The cathode electrode, anode electrode, and beam line apparatuses are now under fabrication. A beam test of the gun will be started soon. The high-voltage test and up-to-date status of the gun development will be presented in detail.
