Residual strength degradation model of 18CrNiMo7-6 forged steel

Residual strength is one of the important properties of materials and is the basis for material fatigue life prediction. In this article, the residual strength of 18CrNiMo7-6, a commonly used material for wind power gears, is degraded with the load of fatigue load. According to the law of fatigue damage generation and development, a residual strength degradation model is proposed. According to the comparison between the test results and the model, the accuracy of the proposed model is high. When the number of loading/total number of cycles is close to 0.7, the residual intensity will change significantly. It is helpful to further study the reliability change of wind power gears under high cycle fatigue.