Interactive Mechanisms of Sulfide Inclusions and Environmental Factors in Low Cycle Fatigue Process of Pressure Vessel Steels in High Temperature Water

摘要

Low cycle fatigue tests were conducted in high temperature water for A533B pressure vessel steels with sulfur contents of 0.013, 0.025 and 0.038 wt. percent respectively. Cyclic stress amplitude response and fatigue resistance as well as influence of strain rate, temperature and dissolved oxygen concentration in water were investigated. Fatigue cracking/fractograhpic features were examined. Sulfide-related environmentally assisted cracking mechanism is discussed.