In order to study the inward flow of surface materials at back-ends of billets during Al-extrusion, a FEM model has been proposed and a computer program, named FEMBA, have been developed for PCs. The model and the program FEMBA have been described in part one. In this work, the program FEMBA has been used as a tool to study the flow of surface materials at the back-end under different conditions. The influence of process parameters on the inward flow has been studied. It is found that thickness of surface layer, temperatures and friction at the pad/billet contact surface have significant influence on the inward flow of surface materials. Ram speed can have some influence. The influence of temperatures of the billet, container and pad has been studied separately.

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