An analytical model for predicting peening stresses with general peening coverage

Shot peen forming is widely used to shape a metallic thin-walled component. It is essential to introduce appropriate residual stresses into the component by controlled peening process. The nonuniform peening stresses under low peening coverage are hardly calculated strictly from elastic-plastic analysis. A method is proposed by hybridizing analytical model and finite element simulation to calculate the peening stresses with general peening coverage. An analytical model is developed based on the expanding cavity model to calculate the whole stress field of single impact and saturation peening stress field firstly. Then an algorithm is proposed to calculate the peening stresses with general peening coverage by mixing the single impact stresses and saturation peening stresses, where a mixing constant which is independent of peening coverage is involved. The determination of the mixing constant can be done by the aid of a few of multiple-impact simulations. The proposed method is performed in different peening conditions. The predicted induced stresses are compared with simulated values. The predicted resultant curvatures of peened plate are compared with experimentally measured values. All of the comparisons show good agreements.