作　　者： ; ; ; ;

机构地区： 江苏大学材料科学与工程学院

出　　处： 《机械工程材料》 2010年第1期13-16,共4页

摘　　要： 运用光学显微镜、扫描电镜和万能电子拉伸试验机等研究了稀土元素钇对A356合金显微组织和拉伸性能的影响。结果表明:稀土钇是A356合金的一种优良变质剂,不但能使初生的α-Al晶粒变得圆整细小,二次枝晶间距减小,而且能使共晶硅由粗大的板条状转变为细小的颗粒状或纤维状;当加入0.4%钇后,A356合金的抗拉强度和伸长率分别达到了298 MPa和9.5%,比未添加钇的合金分别提高了29.6%和21.5%。 The effect of rare earth Y on the microstructure and tensile properties of A356 alloy was studied by using OM, SEM and tensile testing machine. The results indicate that rare earth Y is an excellent modifier for A356 alloy. Y could not only refine primary a-Al phase, make the grain fine and equiaxed, reduce secondary dendrite arm spacing, but also could result in the transformation from striation texture to fibrous eutectic Si. When 0. 4wt% Y was added, the values of the tensile strength ab and elongation δ of A356 alloy reached 298 MPa and 9. 5%, which were increased by 29. 6% and 21.5% respectively, compared with the alloy without adding Y element.

关 键 词： 铝合金 稀土元素 变质处理 显微组织 拉伸性能

领　　域： [金属学及工艺] [一般工业技术] [金属学及工艺]