Replacement of radiation monitors in the lead cells of JMTR Hot Laboratory

Kato, Yoshiaki; Yamamoto, Toshio; Takada, Fumiki; Omi, Masao; Nakagawa, Tetsuya

JAEA-Testing 2008-004, 22 Pages, 2008/06

JAEA-Testing-2008-004.pdf:5.88MB

This report is concerned with replacement of the radiation monitors in the lead cells of JMTR Hot Laboratory in the 2007 fiscal year. It was carried out on two of seven systems of the radiation monitors. The designing, producing, installing, adjusting and inspecting were described.

Effects of radiation-induced stress relaxation on radiation hardening and IASCC Susceptibility in type 316L stainless steel in BWR condition

Miwa, Yukio; Kaji, Yoshiyuki; Tsukada, Takashi; Yamamoto, Toshio; Kato, Yoshiaki; Yonekawa, Minoru; Matsui, Yoshinori

Proceedings of 15th International Conference on Nuclear Engineering (ICONE-15) (CD-ROM), 6 Pages, 2007/04

Radiation-induced stress relaxation (RISR) test under uniaxial loading condition for tensile type specimens was carried out for type 316L stainless steel (SS). The specimens were irradiated in the Japan Materials Testing Reactor at 561 K to three dose levels (0.1-3 dpa) under four displacement constrained condition (prestrain range; 0.06-0.75%) in order to apply residual stress. Radiation hardening behavior and IASCC susceptibility of the RISR-tested 316L SS were examined by slow strain rate testing (SSRT) in oxygenated high temperature water. It was concluded from the SSRT results that the RISR had little influence on the radiation hardening behavior and IASCC susceptibility in the 316L SS. In all specimens, the residual stress rapidly decreased with increasing dose, and the residual stress level after irradiation was much lower than the stress level to initiate IASCC.

Radiation hardening and -embrittlement due to He production in F82H steel irradiated at 250 C in JMTR

Wakai, Eiichi; Jitsukawa, Shiro; Tomita, Hideki*; Furuya, Kazuyuki; Sato, Michitaka*; Oka, Keiichiro*; Tanaka, Teruyuki*; Takada, Fumiki; Yamamoto, Toshio*; Kato, Yoshiaki; et al.

Journal of Nuclear Materials, 343(1-3), p.285 - 296, 2005/08

https://doi.org/10.1016/j.jnucmat.2004.10.167

The dependence of helium production on radiation-hardening and -embrittlement has been examined in a reduced-activation martensitic F82H steel doped with B, B and B+B irradiated at 250C to 2.2 dpa. The total amounts of doping boron were about 60 massppm. The range of He concentration produced in the specimens was from about 5 to about 300 appm. Tensile and fracture toughness tests were performed after neutron irradiation. 50 MeV-He irradiation was also performed to implant about 85 appm He atoms at 120C by AVF cyclotron to 0.03 dpa, and small punch testing was performed to obtain DBTT. Radiation-hardening of the neutron-irradiated specimens increased slightly with increasing He production. The 100 MPam DBTT for the F82H+B, F82H+B+B, and F82H+B were 40, 110, and 155C, respectively. The shifts of DBTT due to He production were evaluated as about 70C by 150 appmHe and 115C by 300 appmHe. The DBTT shift in the small punch testing was evaluated as 50C.

Mechanical property of F82H steel doped with boron and nitrogen

Wakai, Eiichi; Matsukawa, Shingo; Yamamoto, Toshio*; Kato, Yoshiaki; Takada, Fumiki; Sugimoto, Masayoshi; Jitsukawa, Shiro

Materials Transactions, 45(8), p.2641 - 2643, 2004/08

https://doi.org/10.2320/matertrans.45.2641

no abstracts in English

Treatment test of supernatant from sewage sludge by irradiation of high energy electron beams under supersaturation with oxygen

Hosono, Masakazu; Arai, Hidehiko; Aizawa, Masaki*; Shimooka, Toshio*; Yamamoto, Ichiro*; Shimizu, Ken*; Sugiyama, Masahi*

JAERI-M 93-007, 35 Pages, 1993/02

JAERI-M-93-007.pdf:1.23MB

no abstracts in English