Stress corrosion cracking behavior of cold-drawn 316 austenitic stainless steels in simulated PWR environment

The stress corrosion cracking (SCC) behavior of solution-treated and cold-drawn 316 austenitic stainless steels was investigated in simulated pressurized water reactor environment by slow strain rate tensile test. Both cold drawing and Cl addition in simulated primary environment can observably increase SCC susceptibility of 316 austenitic stainless steels. The oxides containing higher Cr concentration initially nucleate on crack tip, and then react with dissolved oxygen and H2O to form the Fe-rich oxides on crack flank during the subsequent crack propagation in abnormal water containing Cl. The deformation twins activated by cold-drawing provide paths to accelerate the oxygen diffusion during SCC.