Prediction of material necking in digital environment

Abstract

Modern production which is based on metal forming tends to the increased analysis of forming processes in digital environment before the actual production set-up. For all these activities, the quality input data of used material is necessary. Simulations of sheet metal forming demand the input data of friction between the analysed objects, flow curve, yield point, material's anisotropy as well as the level and the course of a forming limit curve. Some aspects of predicting the forming limit diagrams in digital environment are discussed in this paper in order to omit expensive and time consuming experimental work. Improved method of numerical determination of FLD’s in digital environment based on the spatial and time determination of material necking is presented. Influential parameters of Marciniak testing procedure such as the coefficient of friction, mesh size and sampling rate of data acquisition in digital environment have been analysed as well.