STRESS-CORROSION CRACKING OF SENSITIZED AUSTENITIC STAINLESS-STEELS IN HIGH-TEMPERATURE WATER

Stress corrosion CraCking (SCC) susceptibility of sensitized austenitic stainless steels, mainly type 304 SS. was investigated in oxygenated high-purity water and borated water below 240-degrees-C. Mainly uniaxial constant load tests were performed on specimens under creviced and uncreviced conditions, and the results were compared with those of creviced constant deflection tests (double U-bend and creviced bent-beam specimens). The results were consistent with each other under creviced conditions, and no difference was observed with the results in high-purity water and borated water. A drastic reduction in time-to-failure and lower critical stress for SCC was observed under creviced constant load tests at 240-degrees-C, and the influence of crevice from the environmental viewpoint for SCC was discussed. The effects of temperature, stress, materials, and SCC test methods were also discussed.