Realistic representation and investigation of charge weld evolution during direct porthole die extrusion processes through FE-analysis

摘要

During the continuous production of aluminium extruded profiles, it is an industrial practice to rely on the billet-to-billet extrusion process. Following this approach, material from different charges joins together while the extrusion of the profile is carried on, forming the charge weld. The section of profile containing welded material must be detected and removed due to the reduced mechanical properties of the product. The aim of this study is to provide guidelines to reduce the elongation of the charge weld by means of geometrical changes of the die. For this purpose, a charge-weld-analysis algorithm has been implemented in the special purpose FE-code PF-Extrude.