热处理和挤压对WE53镁合金组织与力学性能的影响

为提高WE系列生物镁合金的力学性能，采用重力铸造法制备了Mg-5Y-2Nd-1Gd-0.5Zr （质量分数，WE53）镁合金，并对铸态合金进行了固溶处理（T4），固溶＋时效处理（T6）和挤压加工.利用光学显微镜和扫描电子显微镜观察了合金的显微组织，并利用拉伸试验机和显微硬度计测试了合金室温力学性能.结果表明，铸态合金屈服强度为130 MPa，伸长率为10.2%，T6处理可显著提高铸态合金的强度和硬度，降低合金的伸长率；挤压变形明显提高合金的强度和硬度，伸长率与铸态相当.通过适当的热处理和挤压变形可显著改善WE53镁合金的力学性能.

Effects of heat treatment and extrusion on the microstructures and mechanical properties of WE53 magnesium alloy

The Mg-5Y-2Nd-1Gd-0.5Zr （wt%, WE53） magnesium alloy is prepared by gravity casting in order to improve mechanical properties of WE series biodegradable magnesium alloys. Solution treatment （T4）, solution ＋ aging treatment （T6） and extrusion are conducted on the as-cast alloy. Microstructure of the alloy is observed by optical microscopy and scanning electron microscopy. And mechanical properties at room temperature are measured by tensile test machine and microhardness tester. The results show that the yield strength and elongation of the as-cast alloy are 130 MPa and 10.2%, respectively. The strength and hardness of the alloy are apparently enhanced but the elongation is decreased by T6 treatment. Extrusion can improve the strength and hardness of the alloy significantly, and the elongation is close to that of the as-cast alloy. The mechanical properties of the WE53 magnesium alloy can be improved significantly by proper heat treatment and extrusion processes.