Numerical simulation of material failure in single point incremental forming process

The sheet metal parts obtained through single point incremental forming process show a thinning and also there is a high possibility of material failure. In order to avoid the failure of the material during the process, it is a good practice to use numerical simulation through finite element method to prevent this phenomenon. The aim of this paper is to investigate the prediction of the failure moment of the aluminium sheet metal using various failure criteria. Commonly used failure criteria are: Tresca or maximum shear stress criterion, von Mises yield criterion, Hill yield criteria and various invariants of the Cauchy stress tensor. For the numerical simulation of the single point incremental forming process, the semi-finished part is discretized using shell elements which allow determination of material thinning and also it is possible to observe the moment of material failure. This paper will treat also the influence of the wall angle over the moment of material failure. (paper)