中文摘要：

通过SEM、光学显微镜、失重测量、拉伸测试等方法研究了热挤压加工对不同Gd含量的AM50GdX镁合金的显微组织及腐蚀力学性能的影响。结果表明：热挤压后,合金内部出现了具有方向性的平行纤维变形组织;随着Gd含量的增加,AM50GdX镁合金组织中β-Mg17Al12相数量减少而Al2Gd3相数量和体积增加;1%Gd元素对合金耐蚀性提升作用最大;热挤压处理使合金的晶粒细化,从而使拉伸强度提升了接近50%;由于热挤压处理和1%Gd元素的存在大大改善了AM50镁合金的腐蚀剩余强度性能。

英文摘要：

The microstructure and corrosion mechanical properties of hot extrusion treated different Gd addition of AM50 were studied by SEM,optical microscope,weightlessness and tensile test. The results indicated that after hot extrusion treated,the microstructure showed parallel fibers deformation characteristically; β-Mg17Al12 phase decreased and Al2Gd3 phase increased with Gd addition. 1% wt. was the best addition to improve the corrosion property of hot extrusion AM50 magnesium alloy. Due to the hot extrusion,the grain of AM50 magnesium alloy was refined significantly,which improved the tensile strength of AM50 magnesium alloy to about 50%. The corrosion residual strength（ CRS） of AM50 magnesium alloy was improved after 1% Gd. addition and hot extrusion treatment.