Effect of Gd content on microstructure and mechanical properties of Mg-Y-RE-Zr alloys  

作　　者：张奎 李兴刚 李永军 马鸣龙 

机构地区：[1]State Key Laboratory for Fabrication and Processing of Nonferrous Metals,Beijing General Research Institute for Nonferrous Metals

出　　处：《中国有色金属学会会刊：英文版》2008年第A01期12-16,共5页Transactions of Nonferrous Metals Society of China

基　　金：Project(2007CB613705)supported by the National Basic Research Program of China;Project(2006BAE04B01)supported by the NationalScience and Technique Support Program during the 11th Five-Year Period of China.

摘　　要：Four kinds of Mg-Y-RE-Zr alloys with different Gd contents were prepared,and the effect of Gd content on microstructure and mechanical properties of the alloys was researched.Based on the experimental investigation,the compounds at the grain boundaries are mainly Mg_(24)Y_5,Mg_(41)Nd_5,and Mg_5Gd phases.The average grain size of as-cast alloys is 50-60μm.After T4(535℃, 24 h)treatment,Mg_5Gd phases mostly decompose and dissolve into the matrix,and the disperse spotted phases are mainly Mg_(24)Y_5 and Mg_(41)Nd_5 phases.After extruding and ageing(250℃,5 h),the grain size is refined and some grains abnormally grow up to about 40μm.With Gd content increasing,the ultimate tensile strength,yield strength of as-cast alloys and the extruded bars after ageing are improved,but the elongation is decreased.Four kinds of Mg-Y-RE-Zr alloys with different Gd contents were prepared, and the effect of Gd content on microstructure and mechanical properties of the alloys was researched. Based on the experimental investigation, the compounds at the grain boundaries are mainly Mg24Y5, Mg41Nd5, and Mg5Gd phases. The average grain size of as-cast alloys is 50-60 um. After T4 （535℃, 24 h）treatment, Mg5Gd phases mostly decompose and dissolve into the matrix, and the disperse spotted phases are mainly Mg24Y5 and Mg41Nd5 phases. After extruding and ageing （250 ℃, 5 h）, the grain size is refined and some grains abnormally grow up to about 40 um. With Gd content increasing, the ultimate tensile strength, yield strength of as-cast alloys and the extruded bars after ageing are improved, but the elongation is decreased.

关 键 词：挤压成型 合金 微观结构 镁合金 钆合金 

分 类 号：TG146.22[一般工业技术—材料科学与工程]