FEM-based optimization approach to machining strategy for thin-walled parts made of hard and brittle materials

Thin-walled parts are widely used in the aerospace, automotive, and medical industries. High machining efficiency is desired as much of the material needs to be removed. The aggressive machining strategies are often applied but tend to cause poor surface finish, inadequate machining tolerance, and even fracture of workpiece. Thus, it is of vital importance to adopt reasonable machining strategy and choose accurate machining parameters considering of both the machining efficiency and quality. In this paper, an optimization approach to enhance machining efficiency for thin-walled parts made of hard and brittle material without compromising machining quality was proposed. The core idea of the proposed approach is to minimize the maximum stress of the thin-walled part during machining by optimizing the workpiece shape based on finite element method (FEM). The stiffness of the thin-walled parts during machining retains high while the machining induced deformation is small. The optimization approach was experimentally validated on K9 glass, and the maximum deformation of the thin-walled part for the optimal machining strategy decreases significantly compared with that of traditional machining strategy and the total machining time is reduced by 44%.