Stress corrosion susceptibility of 316L in H_2S and Cl~- aqueous solution

摘要

Slow strain rate tests (SSRT) of 316L stainless steel are conducted in H_2S and Cl~- aqueous solution. The effects of test solution parameters such as H_2S concentration, Cl~- content, pH value and test temperature on the susceptibility of 316L stainless steel to sulphide and chloride stress corrosion cracking are studied. These parameters are divided into 6 grades of their own range, and they are combined by Even Design Method to produce 6 test solutions. Testing data are collected automatically by computer and output as the stress elongation curve. Based on areas below the stress elongation curve, stress corrosion susceptive indexes of 316L stainless steel are calculated and equations of stress corrosion susceptive index are regressed by testing data. The microstructure of the specimen fracture in different grade test solutions are analyzed with scanning electron microscope(SEM). The results show that Cl~- is more effective to stress corrosion crack of 316L stainless steel, while H_2S is less effective.