Simulation of 3d residual stress field of shot peening by dynamic finite element analysis

The shot peening process is simulated by FEM using ABAQUS codes. The 3D linear reduced-integration elements are used to predict residual stress fields in the weldments peend by glass beads and steel shots under the same Almen intensity. The effect of Hourglass, dynamic hardening of target material, peening coverage and initial residual stress induced by welding are considered during the simulations. It can been seen from the results that steel-shots peening can produce deeper compressive residual stress layer, but in the condition of higher peening coverage glass-beads peening results in higher average residual compressive stress on the surface of weldments than steel shots. Numerical results also show that a residual compressive stress layer could be produced by shot peening even if there are welding residual tensile stresses existing in the weldments. Therefore, shot peening is an effective method for protecting weldments against stress corrosion crack. The above results provide the basis for studying the mechanism on prevention of stress corrosion cracking in weld joint of 304 type stainless steel by shot peening.