Influence of geometrical conditions on central burst appearance in axisymmetrical drawing processes

Central burst is a common defect in drawing processes. Although other variables are usually involved, it is widely known that central burst appearance is restricted to large die semiangles and small reductions. Several studies have been developed in order to define the ranges of these variables where this defect is expected to occur. In this study, three different cases have been analysed taken into account the results of previous studies. The combination of reductions and die semiangles provides three different situations to be studied. Because the propagation of cracks is a secondary problem in metal forming processes, the main objective in this work is to avoid their occurrence by means of the observation of variables such as the hydrostatic stress and the strain rate.