微量钇对压铸AZ91D镁合金组织及力学性能的影响  

Effect of Minor Yttrium on Microstructure and Mechanical Properties of Die Casting AZ91D Magnesium Alloy

作　　者：徐玉磊[1] 张奎[2] 

机构地区：[1]内蒙古科技大学材料与冶金学院,内蒙古包头014010 [2]北京有色金属研究总院有色金属制备加工国家重点试验室,北京100088

出　　处：《热加工工艺》2018年第1期79-82,87,共5页Hot Working Technology

基　　金：内蒙古自然科学基金面上项目(2014MS0517)

摘　　要：为了提高压铸AZ91D镁合金的力学性能,采用扫描电镜、XRD分析、拉伸性能测试和化学成分测试等方法研究了添加微量稀土Y对压铸AZ91D镁合金组织及力学性能的影响。结果表明：随着Y含量的增加,原强化相Mg_（17）A1_（12）逐渐减少,新强化相A1_3Y和A1_2Y_3等的形成使得合金的抗拉强度逐渐提高。由于在熔炼过程中Y与熔体中的氧反应,起到净化熔体的作用,合金伸长率随着Y含量的增加而增加。A1_3Y和A1_2Y_3等相的形成消耗了A1元素,造成Mg_（17）Al_（12）相较难形成,导致Mg基体粗大,使合金的屈服强度降低。In order to improve the mechanical properties of die casting AZ91D magnesium alloy, the effects of minor yttrium （Y） addition on the microstructure and mechanical properties of the die casting AZ91D magnesium alloy were investigated by using scanning electron microscopy, X-ray diffraction analysis, tensile test and chemical composition test. The results show that with the increase of the Y content, the original strengthening phase of Mg17Al12 gradually decreases, and the tensile strength of the alloy gradually increases with the formation of Al3Y and Al2Y3 strengthening phases. In the melting process, Y and oxygen in melt react to purify the melt, and the elongation of the alloy increases with the increase of Y content. The formation of Al3Y and Al2Y3 phases consumes Al element, and it is difficult to form Mg17Al12 phase and leads to coarse Mg matrix, and the yield strength of the alloy decreases.

关 键 词：压铸镁合金 AZ91D 稀土钇 力学性能 

分 类 号：TG146.22[一般工业技术—材料科学与工程] TG292[金属学及工艺—金属材料]