An Investigation of Local Strain Rate Values during Metal Forming

In order to achieve a high quality of metal forming process, material properties, velocity, stress and strain rate distribution have to be analysed very accurate. Several different approximate methods have been developed for the analysis of cold forming processes. In this paper the visioplasticity method is used to find the strain rate distributions from the experimental data, using the finite-difference method. Specimens of copper alloy were extruded with different lubricants and different coefficients of friction and then the strain rate distributions were analysed and compared. Significant differences in strain rate distributions were obtained in some regions, especially at the exit of the plastic zone.