Effect of stress concentration caused by 3D surface topography on gear bending fatigue life

Abstract Regarding the mechanism by which stress concentration affects gear bending fatigue life prediction, this study employs an integrated approach combining theoretical analysis, experimental testing, and numerical simulation to develop a modified prediction model that incorporates stress concentration effects. First, gear bending fatigue tests were carried out to obtain fatigue life data under various load conditions, and the geometric characteristics of the tooth root were captured via 3D scanning technology. Subsequently, a theoretical model integrating the stress concentration factor was established based on the maximum principal strain criterion. Finally, the accuracy of the modified model was verified by comparing experimental and simulation results. The findings reveal a significant inverse correlation between the stress concentration factor and gear bending fatigue life. Validation data indicate that the modified model achieves an average relative prediction error of 11.2%, indicating a high level of predictive accuracy. This model offers a viable approach for the accurate evaluation of gear fatigue life.