This paper investigates the characteristics of acoustic emission (AE) signals generated by stress corrosion cracking in high temperature primary water (PWSCC) and hydrogen assisted cracking in a nickel base alloy (alloy 600) under constant load. Results demonstrate the possibilities offered by the AE technique in the corrosion field, and show that AE can efficiently be used to detect corrosion initiation and to monitor crack propagation under pressurized water reactor (PWR) conditions. Moreover, it is shown that semi-quantitative information on the PWSCC crack growth rate can be obtained with this technique.
Key words: acoustic emission, PWSCC, hydrogen assisted cracking, alloy 600, high temperature water, PWR, sulfuric acid