Corrosion fatigue crack propagation of high-strength steel HSB800 in a seawater environment

Abstract

Fatigue and corrosion fatigue crack propagation behaviors of high-strength steel, HSB800, were investigated in air and seawater environments. Three-point bending fatigue tests were conducted under various loading conditions at different levels of load frequency and ratio. A fracture model enabling mechanisms-based prediction of corrosion fatigue crack propagation is presented. The results obtained from the model follow the experimental data very well. Validation of the model was also conducted by comparison with other models that used in the analyses of corrosion fatigue crack propagation rates. As shown in results, the corrosion fatigue crack propagation rates in a seawater environment were higher than those in air condition under every loading conditions. These higher corrosion fatigue crack propagation rates were made possibly by the mechanisms of hydrogen embrittlement together with anodic dissolution.