Corrosion Fatigue Crack Growth Behavior of Austenitic Stainless Steels in Seawater Environment

The corrosion fatigue crack growth behavior of 304, 316 and 321 stainless steels in air and seawater at room temperature(RT) - 80 ℃ was studied. The results show that the corrosion fatigue crack growth rate of the three stainless steels in seawater environment was significantly higher than that in air, which was due to the accelerating effects of hydrogen-induced cracking and anodic dissolution in the corrosive environment. The acceleration effect of seawater on fatigue behavior of materials was related to the test parameters: the smaller the magnitude of the stress intensity factor and the lower the loading frequency, the more obvious the acceleration effect of corrosion. The crack growth rate was analyzed based on the Paris formula. The results show that the corrosion fatigue crack growth rate of the materials in seawater at room temperature to 80 ℃ agreed well with the Paris formula.