The influence of dissolved hydrogen and temperature on primary stress corrosion cracking (PWSCC) of alloy 600 was studied at temperature ranging from 310 to 360 °C and hydrogen contents ranging from 0 to 4 ppm using slow strain rate tensile technique (SSRT) and constant
load tensile test. In this study, it was revealed that the PWSCC susceptibility of alloy 600 has a maximum near 3 ppm of dissolved hydrogen at 360 °C and the peak shifts to 1 ppm at 320 °C. The mechanism of the peak shift is not clear yet, however, it might possibly be explained by the change of hydrogen recombination reaction and/or change of the surface film.
Key Words: alloy 600, MA600, stress corrosion cracking, primary water, SCC, PWSCC, dissolved hydrogen, activation energy