The establishment of a failure criterion in cross wedge rolling

Abstract

Internal defects in the cross wedge rolling (CWR) process can lead to the catastrophic failure of products. Using specialised experiments and the explicit dynamic finite element model (FEM), this work investigates the mechanisms of void generation and growth in the cross wedge rolling process. Based on a combined numerical and experimental approach, the morphology of void generation is determined as a function of the workpiece material and three primary parameters in the cross wedge rolling process: the forming angle, α, the stretching angle, β and the area reduction, ΔA. Through the definition of a non-dimensional deformation coefficient, e, a method for predicting the likelihood of void formation is subsequently ascertained and discussed with respect to CWR tooling design and operating conditions.