Finite element simulation of deep rolling and evaluate the influence of parameters on residual stress

摘要

In general, residual stresses in a body can be harmful or useful. Tensile residual stresses are usually harmful which make the surface of the body brittle and decrease the mechanical strength. Whereas compressive residual stresses are usually useful. There are various techniques to improve resistance of parts in fatigue or oscillating loads. One of the most efficient techniques is inducing residual stress layer in the surface of components. Mechanical surface treatments such as deep rolling, shot peening, and laser peening can significantly improve the fatigue behavior of metallic components with high stress. Deep rolling, also can improve surface quality, dimensional accuracy and mechanical properties of the parts. Compressive residual stress generated by the process reduces the tensile stresses during loading into the workpiece. By this process surface finish can be improved in a very high level as well. These two factors, reducing the tensile stress in part through the creation of compressive residual stress and surface finish, Enhance the fatigue life of the piece. The distribution of residual stress induced by deep rolling can be influenced by rolling parameters such as overlap of the rolling tracks, friction coefficient between roller and target plate, deep rolling with constant force, and deep rolling with mechanical tools. In this work the effect of these parameters are studied by finite element simulations. The material used in this work is Ti-6A1-4V.