Investigation of longitudinal welding in port-hole die extrusion

A physical simulation experiment that is capable of reproducing on real-material samples the division of the material flow and the subsequent bonding that arises during multi-hole die extrusion or longitudinal welding of aluminum alloys at elevated temperatures was investigated. The main features of the test as well as some fundamental results was also investigated that give insight into the correlation between weld quality and extrusion process parameters. The simulative test consisted of the upsetting of prismatic specimen with a central hole in which a steel pin is inserted. Deformation was carried out under pseudo plan-strain conditions to approximate a uniform metal flow in all sections. The experiments set up were optimized by 2D and 3D numerical simulations using Forge 2005 to obtain controlled material flow division by varying the dimensions and the geometry of the specimen. The proposed approach can assure careful control of all the involved parameters and ease of conduction.