Abstract: In order to study the effects of preload on the residual stresses induced by surface mechanical rolling treatment (SMRT), the threedimensional finite element models in conjunction with a novel computation framework coupling the explicit dynamics and implicit statics were developed to simulate the process of surface mechanical rolling of AISI 4340steel under preload. At first, the elastic deformation was produced in the finite element model to be surface mechanical rolled by applying the displacement load. Secondly, the displacementpreloaded side was completely constrained for freezing the displacementinduced elastic deformation. On this basis, the surface mechanical rolling of the finite element model with the freezing elastic deformation was then carried out. Lastly, the residual stresses induced by surface mechanical rolling treatment were comparatively studied after the freezing elastic deformation was released. The obtained results show that the surface mechanical rolled materials can produce the unfavorable tensile residual stresses in the treated surface, and the maximum compressive residual stresses can be reduced if the preloading direction is opposite to the direction of rolling pressure. The compressive residual stresses in the subsurface of surface mechanical rolled materials can be further reduced when the preload is released. It is therefore necessary to avoid the preload in the surface mechanical rolling process.

Key words:  surface mechanical rolling treatment; preload; residual stresses; numerical simulation

HU Xing-yuan, WANG Cheng, LI Kai-fa, et al. Numerical study of effects of preload on the residual stresses induced by surface mechanical rolling treatment［J］.Journal of Mechanical & Electrical Engineering, 2021,38(8):1064-1069.