Study on residual stress and deformation of titanium alloy thin-walled parts by ultrasonic shot peening

After ultrasonic shot peening (USP) treatment, the titanium alloy thin-walled parts will induce strengthening residual stress. Simultaneously, the parts will undergo bending deformation due to the residual stresses, which can affect subsequent assembly and usage. Therefore, it is necessary to effectively predict the deformation induced by USP. Aiming at prediction of residual stress and deformation of USP, the experiments of titanium alloy specimen were carried out in this paper. The surface residual stress and the variation law of residual stress along the depth were obtained by using the corrosion stress delamination method. The residual stress was characterized by constructing the functional relationship between residual stress and depth under different process parameters. Furthermore, by establishing a three-dimensional finite element model of workpiece, the deformation of the specimen was obtained. Also the relationship among amplitude, maximum deformation and shot diameter was analyzed. Comparative results between experiments and simulations indicate that the deformation trends are consistent. Furthermore, it was observed that the maximum deformations occur in the central region of the thin plate. The research is validated that the residual stress characterization model can predict the deformation of titanium alloys thin-walled parts due to the USP. Therefore, this model can achieve residual stress field reconstruction and deformation prediction analysis.