Effect of induction heating composite shot peening on fatigue crack growth behavior, wear performance of 20CrMnTi gear steel

Shot peening is a commonly used surface-strengthening method, generates plastic deformation on a material surface, introduces residual compressive stress, and improves the fatigue performance of the materials. It is widely used in the surface strengthening of materials. However, to further promote the surface strengthening effect, this article proposes a new induction heating composite shot peening (IHCSP) method that achieves the surface composite strengthening of 20CrMnTi gear steel. Based on tensile, fatigue crack propagation and friction tests, combined with scanning electron microscopy (SEM) and optical microscopy (OM) characterization methods, the influence mechanism of IHCSP on mechanical properties, fatigue crack propagation resistance and wear resistance of 20CrMnTi gear steel was revealed.The results showed that the IHCSP improves the tensile strength and yield strength of the material, reduced the friction coefficient and wear volume by 3.96% and 34.8% respectively, decreases the crack growth rate and increased the fatigue life to 85369 cycles. This study proves that IHCSP can significantly improve the fatigue properties of 20CrMnTi gear steel, highlighting the effectiveness of the IHCSP surface-strengthening method.