Effects of S, P, C and Ti addition on slow strain rate tests properties of irradiated high purity type 304 alloys

Nakano, Junichi; Nemoto, Yoshiyuki  ; Numata, Masami; Taguchi, Taketoshi ; Tsukada, Takashi 

To evaluate the effects of minor elements on Irradiated Assisted Stress Corrosion Cracking (IASCC), type 304 stainless steels with high purity were fabricated and minor elements, Si, S, P, C, Ti, were added. After neutron irradiation to 3.510 n/m (E1MeV) in the JRR-3, Slow Strain Rate Tests (SSRT) were performed in oxygenated water at 561 K. Subsequently, fracture surface examination and hardness test were performed. The results of the steels with Si and C have been reported already. The specimen with P showed approximately 15% in Intergranular Stress Corrosion Cracking (IGSCC) fraction which was the lowest in the all specimens. P addition may reduce susceptibility to IASCC. IGSCC fraction of the specimen with S was similar to that of the specimen irradiated to 6.710 n/m. Hardness in the grains was similar to that at grain boundaries. Hardness of the specimens with C was higher than that of the specimens without C.