Description of numerical techniques with the aim of predicting the sheet metal blanking process by FEM simulation

A numerical formulation of the blanking process in 2D is presented in this article. A finite element software called BlankForm has been developed to simulate the blanking process. Several approaches to model ductile damage and fracture have been investigated and are presented in this paper. In particular, some details are provided about a discrete cracking method that has been developed to take the propagation of one or several cracks into account. Our formulation is evaluated on an axisymmetric blanking experiment. The importance of remeshing is demonstrated. Coupled and uncoupled damage models are benchmarked, and two methods for fracture simulation are analysed, namely the previous discrete cracking method, and a widely used method in blanking applications, the element kill method. It is shown that more realistic results are obtained when the discrete cracking method is used.