Numerical modeling of multipoint blanking process of electrical steel

Abstract

AbstractA new method of forming using multipoint blanking, which can reduce cutting forces was discussed. In the processes of punching and blanking magnetic materials, an important problem is excessive and irregular wear of the cutting edges of the punches. The contribution proposes multipoint initiated punching using specially designed punches, which aims to significantly reduce the punching forces needed to separate the material. The FEM method was used to analyze the physical phenomena occurring during the process. The updated Lagrange description was used to describe the phenomena at a typical incremental step. The states of strain and strain rate are described by nonlinear relationships without linearization. The description of the nonlinearity of the material was made with an incremental model taking into account the influence of the history of strain and the strain rate. The condition of the material after the previous treatments was also taken into account by introducing the initial states: displacements, stresses, strains, and their velocities. Analyses of the impact of the geometry of blanking tools on the values of stresses, deformations, and blanking forces were carried out. Fatigue analyses were carried out for the proposed tools. The research results may be useful for the design of modern blanking tools used in the processing of electrical materials.