Experimental Investigation on 7075 Aluminium Response during Thixoextrusion

Abstract:

The deformation behavior of semi-solid aluminium alloy is strongly dependent on the microstructure. This paper illustrates several experimental research works concerning thixoextrusion of 7075 aluminium alloy which was carried out at “Arts et Métiers ParisTech” of Metz. The microstructure obtained by two reheating systems and flow behavior during thixoextrusion tests were investigated. To minimize the heat losses, a sample obtained from a direct extruded bar is inserted in a die for reheating in semisolid state and for thixoextrusion. Reheating the steel die and the aluminium billet placed into the die at the same time using an induction furnace provides rapidly a very homogeneous microstructure suitable for thixoforming. During the experimental re-heating process, the temperature was directly controlled using thermocouples for temperature measurements in the sample and also in the die. The experimental results on extrusion load and microstructure evolution of the component are reported.

• Periodical: Solid State Phenomena (Volumes 192-193)
• Pages: 149-154
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.192-193.149
• Online since: October 2012
• Authors: Adriana Neag, Véronique Favier, Mariana Pop, Régis Bigot
• Keywords: 7075 Aluminum Alloy, Microstructure, Semi-Solid, Thixoextrusion

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