Extrusion of Short Aluminium Billets - Simulation and Semi-Pilot Test

Abstract

A die setup for direct hot extrusion of extra-short aluminium alloys billets used in semi-pilot plant tests was simulated using DEFORM ™ 2D/3D software and results were compared with experiment. A die setup without welding chamber proved to shorten charge-weld to such extend that most of material could be recovered as usable samples. Having good agreement between simulated and experimental results of two tested die setups (with and without welding chamber) the effect of temperature on length of charge-weld was evaluated. A main drawback of die setup without welding chamber is too short and, consequently, too week charge-weld. Since many extruded profiles need to be stretched after cooling, die setup without welding chamber is not applicable for commercial production. Application of die setup without -or with shallowwelding chamber is limited to flat profiles with simple and symmetrical geometry like round or rectangular bars where mixing of extruded material is not crucial for the profiles properties.

Simulation Upper Bound Theorem to Prediction Extrusion Load

“…Kang and Yang [6,7] found the unsteady three dimensional extrusion of square portion and "H" portion, and found the extrusion force, strain rate, and temperature distributions. Ján Španielka et al [8] die setup for direct hot extrusion of extra-short aluminium alloys billets used in semi-pilot plant tests was simulated using DEFORM ™ 2D/3D software and results were compared with experiment. S. T. Oyinbo et al [9] The flow of metal, consequently load, is largely influenced by the geometry of the die and hence the geometric shape of the tools is the main factor by which an optimum load can be developed.…”