High-Cycle Fatigue Behavior and Fatigue Strength Prediction of Differently Heat-Treated 35CrMo Steels

In order to obtain the optimum fatigue performance, 35CrMo steel was processed by different heat treatment procedures. The microstructure, tensile properties, fatigue properties, and fatigue cracking mechanisms were compared and analyzed. The results show that fatigue strength and yield strength slowly increase at first and then rapidly decrease with the increase of tempering temperature, and both reach the maximum values at a tempering temperature of 200 degrees C. The yield strength affects the ratio of crack initiation site, fatigue strength coefficient, and fatigue strength exponent to a certain extent. Based on Basquin equation and fatigue crack initiation mechanism, a fatigue strength prediction method for 35CrMo steel was established.

Automated summary

Different heat treatment procedures were applied to 35CrMo steel in order to obtain the optimum fatigue performance. The microstructure, tensile properties, fatigue properties, and fatigue cracking mechanisms were compared and analyzed. The results showed that both the fatigue strength and yield strength of the steel reached the maximum values at a tempering temperature of 200 degrees C.