Competitive effect of residual stress and surface roughness on the fatigue life of shot peened S42200 steel at room and elevated temperature

The effect of shot peening (SP) on the fatigue life of S42200 steel at room and elevated temperature is investigated. The fatigue test is carried out on a high temperature rotating bending tester. Surface integrity characterization is used to study the effect of SP on surface properties. Furthermore, Finite Element Method (FEM) combined with a fatigue damage model, namely Zheng Equation, is proposed to predict the fatigue life. The results show that SP effectively improves the fatigue life of S42200 steel under all temperatures. However, at lower temperature, higher strength SP leads to higher fatigue resistance, while at higher temperature, lower strength SP leads to higher fatigue resistance. This can be explained by the competitive effect of surface roughness and compressive residual stress (CRS) relaxation on the local stress concentration. This research can be a good guide to the application of SP at different temperatures.

Automated summary

The effect of shot peening on the fatigue life of S42200 steel at different temperatures was investigated. The fatigue test was conducted using a high temperature rotating bending tester. Surface integrity characterization was employed to analyze the impact of shot peening on surface properties. Additionally, a finite element method combined with the Zheng Equation fatigue damage model was proposed to predict the fatigue life. The results demonstrated that shot peening effectively enhanced the fatigue life of S42200 steel, with the impact varying depending on the temperature.