Nonlinear finite element analysis of machining and sheet metal forming

Simulations are presented of machining and multistage sheet metal forming that improve on the accuracy of existing approaches by incorporating accurate representations of additional physical phenomena. In the finite element simulation of machining, chip formation is simulated without using a separation criterion. This capability has been successfully used to investigate fundamental aspects of machining such as the shape of the primary and secondary shear zones, chip curl, the size effect, and the uniqueness of machining. The analysis of multistage forming incorporates the effects of material property changes due to heat treatments between forming stages. Results of simulated forming operations are employed to evaluate the effectiveness of intermediate die shapes and heat treatments in improving the sheet metal formability. It is found that intermediate heat treatments enhance the ability of intermediate die shapes to promote uniform deformation of the sheet.