Investigation of Process Parameters for the Backward Extrusion of Arbitrary-Shaped Tubes from Round Billets Using Finite Element Analysis

Process simulation for the backward extrusion of internally arbitrary-shaped tubes from circular billets is presented in this article. ABAQUS/Explicit finite element method has been used to analyze the problem. This kind of analysis has been done before using analytical methods such as the upper bound theorem. However, the FEM solution presented here is the first of its kind. Values of stress, strain, and spatial velocity at different points in the deformation field were obtained. To observe the flow of the material during the process, grid deformations were also produced for the backward extrusion using the FEM package. Circular shape for the initial billet and arbitrary shapes for the final tube’s cross sections were considered and FEM solutions were given for each. The shapes considered were elliptical, rectangular, and circular-shaped tubes and circular billets. The variation of extrusion load for the backward extrusion process was obtained for different values of reduction of area, aspect ratio, and friction factor. Also, the effect of these parameters on velocity field and free surface configuration were investigated in this simulation. The results produced from this work were compared with the theoretical and experimental results of other workers and good agreements were observed and some improvements in some of the results were also seen.