Stress corrosion cracking and life prediction evaluation of austenitic stainless steels in calcium chloride solution

The stress corrosion cracking (SCC) susceptibility of austenitic stainless steels (SS) in calcium chloride (CaCl2) solutions was Studied using a constant-load method. Initiation and propagation of stress corrosion cracks were examined using fractography. The distribution of cracks was classified A physical cracking was introduced, and creep deformation measurements were performed. The steady-state strain rate (epsilon(ss)) obtained from the corrosion elongation curve (elongation-vs-time curve) showed a linear function of time to failure (t(f)). This implied that epsilon(ss) can be applied as a parameter for prediction of t(f). Furthermore, epsilon(ss) below which no failure occurs within a laboratory time scale was estimated. Based on results obtained, the critical values of stress (sigma) below which no SCC occurred were evaluated. Based upon creep measurements in a noncorrosive environment, the influence of environment on epsilon(ss) was more than fivefold. Cracking characteristics were divided into three categories according to the crack initiation distribution Transgranular cracking predominated at relatively low sigma and epsilon(ss).