Experimental Study on Fatigue Crack Growth and Residual Strength of Steel 30CrMnSiNi2A under Mixed Corrosive Environments
The effects of five single and three mixed corrosive environments on the fatigue crack growth and residual strength of steel 30CrMnSiNi2A were experimentally studied. The crack growth rates in corrosive environments, obtained by using Paris equation, were compared with crack growth rate in lab air. The results showed that the interactions of aggressive environments with fatigue loads caused the accelerations of fatigue crack growth rates in steel 30CrMnSiNi2A. But the effects of various environments on the fatigue crack growth rate are different. Among the environments the most detrimental one was oil-box zone, followed by cookroom&washroom, tank seeper, 3.5%NaCl, moist air, high altitude and dried air. Also, the test data showed the less effect of various corrosive environments on critical crack length, that is, no direct infection of corrosive environments on residual strength capability dominated by fracture toughness.