Post irradiation examination of type 316 stainless steels for in-pile Oarai Water Loop No.2 (OWL-2)

Shibata, Akira ; Kimura, Tadashi ; Nagata, Hiroshi ; Aoyama, Masashi; Kanno, Masaru; Omi, Masao

Type 316 stainless steels (SSs) were used for tube material of the Oarai water loop No.2 (OWL-2) in the reactor. But data of highly irradiated Type 316 SSs has been insufficient since OWL-2 was installed. Therefore surveillance tests of type 316 SSs which were irradiated up to 3.4 10 n/m in fast neutron fluence (1 MeV) were performed. But type 316 SSs were widely used in JMTR, then additional data of type 316 SSs irradiated higher was required. Therefore PIEs of type 316 SSs surveillance specimens which were irradiated up to 1.0 10 n/m in fast neutron fluence were performed and reported in this paper. Tendency of results has good agreement with results of 10-10 n/m in fast neutron fluence. More than 37 % in total elongation was confirmed in all test conditions. It is confirmed that type 316 SS irradiated up to 1.0 10 n/m in fast neutron fluence has enough ductility as structure material.