Similarity of Cold Work and Radiation Hardening in Enhancing Yield Strength and SCC Growth of Stainless Steel in Hot Water

摘要

Neutron irradiation influences stress corrosion crack (SCC) growth of stainless steels in multiple ways. From a sound understanding of SCC under unirradiated conditions, the most likely roles of irradiation involve radiolysis, radiation hardening, radiation segregation, and radiation creep relaxation. When the contribution of radiolysis to increased corrosion potential is effectively eliminated by high H_2 fugacity in PWRs or NobleChem + H_2 in BWRs, there is a greatly diminished influence of radiation segregation (esp. Cr depletion). However, the role of radiation hardening persists under these conditions, and therefore is of special interest. Based on the hypothesis that the primary role of radiation hardening is to increase the yield strength, studies have been performed on cold worked stainless steel, and show a similar effect on SCC growth rates at low and high corrosion potential.