Development of test techniques for in-pile SCC initiation and growth tests and the current status of in-pile testing at JMTR

Ugachi, Hirokazu ; Kaji, Yoshiyuki  ; Nakano, Junichi*; Matsui, Yoshinori ; Kawamata, Kazuo; Tsukada, Takashi ; Nagata, Nobuaki*; Dozaki, Koji*; Takiguchi, Hideki*

Irradiation assisted stress corrosion cracking (IASCC) is one of the critical concerns when stainless steel components have been in service in light water reactors (LWRs) for a long period. In the research field of IASCC, mainly PIEs for irradiated materials have been carried out, because there are many difficulties on SCC tests under neutron irradiation. Hence as a part of the key techniques for in-pile SCC tests, we have embarked on a development of the test technique to obtain information concerning effects of applied stress level, water chemistry, irradiation conditions, etc. In this conference, we describe the developed several techniques, especially control of loading on specimens, monitoring technique of crack initiation, propagation and water chemistry, and the current status of in-pile SCC tests using thermally sensitized materials at JMTR.