Effect of the Extrusion Conditions on the Microstructure and Mechanical Properties of Indirect extruded Mg-Zn-Y Alloy with LPSO Phase

摘要

Mg alloys are the lightest commercial structural alloys and have excellent specific strength and stiffness characteristics. Due to its good castability, the die casting process has been established for the fabrication of various automobile components such as instrumental panels and seat frames. In particular, the application of Mg alloys to a conventional direct extrusion process is not considered to be cost-effective mainly due to their low extrudability. The indirect extrusion process is free of friction between the billet and the container; hence, the extrusion pressure as well as surface cracking can be reduced considerably compared to the direct extrusion process, leading to its implementation at lower temperatures and higher speeds. In this study, Mg-Zn-Y alloy was subjected to the direct and indirect extrusion processes and the effects of the processing conditions on the microstructure and mechanical properties were investigated.