Investigation of the effect of extrusion process on the microstructure an‎d mechanical properties of Mg-Zn-Ca-La allloy

10/22/2025 12:00:00 AM

Magnesium alloys have recently attracted significant attention in various industries such as transportation, aerospace, an‎d biomedical equipment due to their low density, high specific strength, good recyclability, an‎d biocompatibility. However, their limited ductility an‎d relatively poor mechanical properties at room temperature remain major challenges in the development an‎d widespread application of these alloys. To overcome these limitations, plastic deformation processes—particularly hot extrusion—can play a crucial role in refining the microstructure an‎d improving the mechanical behavior of magnesium alloys. In this study, a magnesium-based alloy containing zinc, calcium, an‎d lanthanum was prepared by melt casting, followed by a homogenization treatment. The prepared samples were then subjected to hot extrusion at an optimized temperature. After extrusion, microstructural characterization was carried out using optical microscopy an‎d scanning electron microscopy, while X-ray diffraction (XRD) analysis was performed to identify the phases. In addition, mechanical tests including tensile testing, microhardness measurement, an‎d wear testing were conducted on both as-cast an‎d extruded samples to eva‎luate the effect of the extrusion process on mechanical behavior. The results revealed that the extrusion process significantly refined the grain size, enhanced the uniform distribution of secondary phases, an‎d led to a substantial improvement in yield strength, ultimate tensile strength, an‎d surface hardness compared to the as-cast samples. Moreover, wear tests showed that the wear resistance of the extruded samples increased considerably, with the reduction in wear rate attributed to microstructural refinement an‎d enhanced surface strength. The presence of lanthanum also played an important role in phase stability an‎d microstructural improvement. Overall, the findings of this study demonstrate that hot extrusion is an effective method for improving the mechanical properties of magnesium alloys alloyed with zinc, calcium, an‎d lanthanum, paving the way for their broader application in industrial an‎d engineering fields.

آلياژ منيزيم، فرآيند اكستروژن، ريزساختار، خواص مكانيكي، لانتانيم

Magnesium alloy; Extrusion process; Microstructure; Mechanical properties; Lanthanum

ehsan bazrkar

Dr. maryam salehi