Numerical Simulation and Experimental Investigation on Thixo-Backward Extrusion of 7075 Aluminium Alloy

Abstract:

The thixoextrusion process could become an important technique to extend the complexity of extruded profiles. However, the complex thixotropic flow behavior of semi-solid, during thixoextrusion is still partly characterized. The study described in this paper investigates thixoextrusion for 7075 aluminium alloy at different temperature conditions. A complete die filling and a good surface state of parts was obtained at high solid fraction (f_S = 0.70), in heated dies, for an extrusion ram speed of 416 mm/s. The thixoextrusion process is simulated using the finite element code Forge2009©. The constitutive equation used for these simulations is based on a micro-macro model for the semi-solid evolution. The tendency of the experimental curves evolution, preserving the same parameters of the micro-macro constitutive model, for each values of solid fraction, was reproduced, except the last step of the ram displacement.

• Periodical: Advanced Engineering Forum (Volumes 8-9)
• Pages: 269-276
• DOI: https://doi.org/10.4028/www.scientific.net/AEF.8-9.269
• Online since: June 2013
• Authors: Adriana Neag, Véronique Favier, Liviu Nistor, Régis Bigot
• Keywords: 7075 Aluminum Alloy, Numerical Simulation, Semi-Solid, Thixoextrusion

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