Integrated computational modeling of electromechanical coupling corrosion behavior in titanium alloys

Titanium alloys are prone to failure under the coupling effect of machinery and environment, and the experimental research on stress corrosion is time-consuming and expensive. This study utilized a multi-physics field coupling model to reveal the electrochemical corrosion behavior of Ti80, TC4, and TA15 titanium alloys under tensile loading. The results indicated that the von Mises stress at the corrosion defect dominated the electrochemical heterogeneity, and the corrosion was quasi-uniform under low strain; when the tensile strain exceeded the critical threshold (Ti80: 0.4%, TC4: 0.6%, TA15: 0.425%), stress concentration triggered accelerated local anode dissolution, resulting in a negative shift in potential, and the corrosion entered a self-accelerating cycle. The Ford-Anderson model was used to quantify the crack propagation kinetics, and the prediction was consistent with the experimental results. This electromechanical coupling mechanism provides a new idea for predicting and preventing stress corrosion cracking in titanium alloys.