The degradation rule of 35CrMo steel was studied based on the development of the damage in the material under cyclic loading, and the Schaff model to describe the degradation of tensile residual strength of 35CrMo steel was presented. Large amounts of experimental data had been employed to support this model and the comparisons between predictions and experiments demonstrate that this model has better capacity of predicting the degradation of tensile residual strength. The distribution of the residual strength after different cycle numbers was studied,and three-parameter Weibull function was presumed. With the increase of the cycle numbers, the scale parameters and location parameters of the Weibull distribution are reduced, and the shape parameters remain unchanged.

power degradation model, residual strength, three-parameter Weibull distribution, 35CrMo steel