Research On Forming Process And Reinforcement Technology Of High Strength Magnesium Alloy

Magnesium alloy is the lightest metal structural materials in practical applications, has both a high specific strength and stiffness and fatigue strength, also has good electrical conductivity, thermal conductivity and magnetic shielding. It is one of the ideal structural materials which is used to achieve lightweight equipment. The paper was prepared Mg-7Gd-5Y-1Nd-1Zr alloy by traditional smelting process and simulated the stress-strain curve of Mg-7Gd-5Y-1Nd-1Zr alloy on different temperatures and different extrusion rate by DEFORM-3D software, further strengthen the Mg alloy by extrusion process, evaluated the mechanical properties of the alloy by tensile test, observed the microstructure characteristics and fracture appearance of the Mg alloy by OM and SEM. The optimization of strengthening process was selected by contrast test of different processes to reinforce Mg-7Gd-5Y-1Nd-1Zr alloy.The research results showed that, the addition of rare earth elements Gd, Y, Nd and zirconium to magnesium decreases the grain size, thus effectively intensifies the mechanical properties. Because the magnesium alloys which was prepared by casting process can not meet the needs of aerospace field, this paper through the processing methods of heat treatment, extrusion and pre-stretch materials to reinforced magnesium alloys. Numerical simulation results of extrusion process showed that the best technology of extrusion speed of Mg-7Gd-5Y-1Nd-1Zr alloy was2.75mm/s at490℃.The strength of casting magnesium alloy is generally low, so is casting rare earth magnesium alloy. The stretch-strength of casting Mg-7Gd-5Y-1Nd-1Zr alloy is only about220MPa. Ultimately, through the extrusion process and pre-stretching process, the stretch-strength of alloy is raised to about410MPa.