Rapid estimation of ductile crack formation in cross-wedge rolling

Abstract

This study investigates the problem of predicting material cracking in cross-wedge rolling (CWR). Fifty-four cases were analyzed using the finite element method (FEM), and maximum values of the damage function were determined. Based on the results obtained from simulations, nomographs were created to allow for quick and easy determination of the maximum damage function values depending on the basic CWR parameters, mainly the forming angle, spreading angle of the wedge, and deformation ratio. The rotary compression test of a cylindrical sample was used to determine the critical damage values for the C45 grade steel formed in the temperature range 950–1150 °C. For the fracture condition to occur, it was assumed that the damage value should be higher than the critical damage value given by the damage function. This hypothesis was experimentally validated. The results of the experiments show good agreement with the numerical results of material fracture obtained with the method described in this study.