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

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 (Ε˙_SS) obtained from the corrosion elongation curve (elongation-vs-time curve) showed a linear function of time to failure (t_f). This implied that Ε˙_SS can be applied as a parameter for prediction of t_f. Furthermore, Ε˙_SS below which no failure occurs within a laboratory time scale was estimated. Based on results obtained, the critical values of stress (σ) below which no SCC occurred were evaluated. Based upon creep measurements in a noncorrosive environment, the influence of environment on Ε˙_SS was more than fivefold. Cracking characteristics were divided into three categories according to the crack initiation distribution. Transgranular cracking predominated at relatively low σ and Ε˙_SS.