The effects of grain boundary carbide density and strain rate on the stress corrosion cracking behavior of cold rolled Alloy 690

The effects of grain boundary carbide density and strain rate on stress corrosion cracking (SCC) initiation susceptibility of cold rolled 690 were evaluated in 360 °C hydrogenated water using slow strain rate tensile (SSRT) tests. The improvement in SCC resistance of a thermally treated microstructure over that of a solution annealed microstructure indicates that grain boundary carbides have a mitigating effect in cold rolled Alloy 690. The effect of grain boundary carbides is dependent on the cold rolling orientation of sample. Slower strain rate aggravates SCC initiation by enhancing the environmental component of SCC.