Evaluating techniques and phenomena of Stress Corrosion Cracking (SCC) in Light Water Reactors (LWRs); SCC evaluating techniques for predicting core internal and pipe aging of LWRs, technical data collection (Contract research)

Yamamoto, Masahiro; Kato, Chiaki; Sato, Tomonori; Nakano, Junichi; Ugachi, Hirokazu; Tsukada, Takashi; Kaji, Yoshiyuki; Tsujikawa, Shigeo*; Hattori, Shigeo*; Yoshii, Tsuguyasu*; et al.

JAEA-Review 2012-007, 404 Pages, 2012/03

JAEA-Review-2012-007.pdf:36.72MB

There are many LWRs which have been operated for more than 20 years in Japan and it is expected that technique corresponding to aging plants are necessary established for safety operation in LWRs. A lot of troubles related to SCC are reported and many investigations are concerned with SCC mechanism and technical evaluation. In this paper, those research data were collected as possible widely and reviewed systematically. Current circumstances concerned with SCC in LWRs were reviewed specifically as follows: SCC incidents, SCC evaluation methods for crack initiation and propagation, the investigations concerned with SCC mechanism and monitoring technique for corrosive environment. Influences with reactor types (BWR, PWR), materials (stainless steels, Ni alloys) and SCC evaluating methods (laboratories and actual plants) were summarized as graphs and tables easy to understand in common/difference points concerned with SCC. From these arranged results, future themes were considered and remarked SCC phenomenon was summarized in actual plants. As for SCC evaluations under the accelerate conditions in the laboratory test, it was suggested that a computational prediction and modeling including statistical technique and microscopic analysis in crack initiation were important. Furthermore it was suggested that monitoring techniques predicting SCC initiation and grasping plant circumstance in operation and feasibility in actual plants were important.

High-pressure neutron diffraction experiments at TAKUMI in J-PARC

Abe, Jun; Hattori, Takanori; Arima, Hiroshi; Sano, Asami; Fukazawa, Hiroshi; Utsumi, Wataru; Komatsu, Kazuki*; Arakawa, Masashi*; Iizuka, Riko*; Kagi, Hiroyuki*; et al.

no journal, , 

In order to confirm the feasibility of high-pressure neutron diffraction at TAKUMI, we have performed a number of R&Ds using a various high-pressure devices. Optimization of materials such as anvil and pressure medium and developments of collimators have made possible reduction of background and contamination noise. Incident and diffracted neutron beams travel through high-pressure device, which causes attenuation of neutron. We investigated the method of attenuation correction.

Systematization of assessment techniques of stress corrosion cracking for in-vessel components and piping in BWRs and PWRs

Kato, Chiaki; Yamamoto, Masahiro; Tsujikawa, Shigeo*; Hattori, Shigeo*; Yoshii, Tsuguyasu*; Kudo, Takeo*; Nemoto, Rikio*; Akashi, Masatsune*

no journal, , 

There are many LWRs which have been operated for more than 20 years in Japan and it is expected that technique corresponding to aging plants are necessary established for safety operation in LWRs. A lot of troubles related to SCC are reported and many investigations are concerned with SCC mechanism and technical evaluation. In this paper, those research data were collected as possible widely and reviewed systematically. Current circumstances concerned with SCC in LWRs were reviewed specifically as follows: SCC incidents, SCC evaluation methods for crack initiation and propagation, the investigations concerned with SCC mechanism and monitoring technique for corrosive environment. Influences with reactor types (BWR, PWR), materials (stainless steels, Ni alloys) and SCC evaluating methods (laboratories and actual plants) were summarized as graphs and tables easy to understand in common/difference points concerned with SCC. From these arranged results, future themes were considered and remarked SCC phenomenon was summarized in actual plants.