Optimization of shot peening parameters for blades based on the constraint of equivalent residual stress-induced deformation

As a surface-strengthening technique, shot peening increases the compressive residual stress in the workpiece. In this paper, how to obtain specific residual stresses to reduce blade deformation by controlling the shot peening parameters was investigated. Based on the cosine function describing the residual stress depth distribution, the equivalent residual stress was calculated. The effect of shot peening parameters (air pressure, flow rate, nozzle speed, and distance) on the equivalent residual stress was modeled. Then a finite element model of the equivalent residual stress-induced deformation of the blade was established, and the effect of equivalent residual stress on blade deformation was investigated via the model. The residual stress domains that make the deformation less than 0.03 mm were obtained by the inverse solution of the exhaustive method, then the optimized parameter of shot peening was also obtained, and the accuracy of the optimization method was verified by shot peening tests. This method can provide technical support for the control of deformation caused by shot peening of blades.