Metallurgical and Engineering Challenges in Magnesium Extrusion

Abstract:

AZ 31 Magnesium alloy was extruded under industrial conditions into both a solid shape and a hollow profile. A microstructure analysis of the solid shape revealed a bimodal grain distribution. The FEM process simulation was performed for double hat hollow profile, extruded through an eight-port-hole die using the modified flow stress model from literature. This allowed us to make a prediction of the extrusion process state variables. Additionally, a numerical simulation revealed some shortcomings in terms of a lack of predictive capabilities for extrusion welding. The integrity of the welds was analyzed using metallography techniques. The search for better mechanical properties has propelled alloy development research. Workability evaluations of new Magnesium alloys ZE20, ZE50 and ZE80 containing Zinc and Cerium were performed using compression tests under various temperature and strain rate conditions.

• Periodical: Key Engineering Materials (Volume 585)
• Pages: 3-10
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.585.3
• Online since: December 2013
• Authors: Wojciech Z. Misiolek
• Keywords: Extrusion, Extrusion Welding, Mg Alloy, Microstructure, Rare Earth Alloying Additions

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