The influence of yield strength on stress corrosion cracking in stainless steel is important because of surface cold work, bulk cold work, weld shrinkage strain, and irradiation hardening. To this end, stress corrosion crack growth rate measurements were performed in high temperature, ultra high purity water on unsensitized stainless steels (and alloy 600) of various grades and compositions as a function of heat, yield strength (cold work), martensite content, corrosion potential, temperature, and hydrogen fugacity. SCC growth rate responded to changes in yield strength, corrosion potential, and temperature - and was substantially independent of the martensite content per se, and the hydrogen fugacity (or hydrogen permeation rate). Unlike commercial heats, a model "stainless steel" alloy containing 5% Si showed high growth rates, little effect of corrosion potential, and little decrease in growth rate with decreasing stress intensity factor.
Key Words" stainless steel, stress corrosion cracking, high temperature water, crack growth rate, corrosion potential, water purity, stress intensity factor, weld residual strain, cold work, sensitization.