Comparison of Sb and Sr on modification and refinement of Mg_2Si phase in AZ61-0.7Si magnesium alloy  

作　　者：杨明波 潘复生 沈佳 白亮 

机构地区：[1]Materials Science and Engineering College,Chongqing Institute of Technology [2]Materials Science and Engineering College,Chongqing University

出　　处：《中国有色金属学会会刊：英文版》2009年第2期287-292,共6页Transactions of Nonferrous Metals Society of China

基　　金：Project(50725413) supported by the National Science Fund for Distinguished Young Scholar in China;Project(2007CB613704) supported by the National Basic Research Program of China;Projects(2006AA4012-9-6, 2007BB4400) supported by the Chongqing Science and Technology Commission of China

摘　　要：The effects of Sb and Sr on the modification and refinement of Mg2Si phase in an AZ61-0.7Si magnesium alloy were investigated and compared. The results indicate that the difference of Sb and Sr in the modification and refinement of Mg2Si phase is significant. Addition of 0.4%Sb(mass fraction) to AZ61-0.7Si alloy can refine but not modify Mg2Si phase. Oppositely,by addition of 0.12%Sr to AZ61-0.7Si alloy,the Mg2Si phase changes from initial coarse Chinese script shape to fine granule and/or irregular polygonal shape. Accordingly,the Sr-modified AZ61-0.7Si alloy exhibits higher tensile and creep properties than the Sb-modified one. The difference of Sb and Sr in the modification and refinement of Mg2Si phase is possibly related to the following two aspects:1) the disregistry at(100)Al4Sr//(100)Mg2Si is lower than that at(0001)Mg3Sb2//(111)Mg2Si(0.69% vs 1.72%) and 2) the onset crystallizing temperature of the Sr-modified AZ61-0.7Si alloy is lower than that of the Sb-modified one(603.1 ℃ vs 606.9 ℃).The effects of Sb and Sr on the modification and refinement of Mg2Si phase in an AZ61-0.7Si magnesium alloy were investigated and compared. The results indicate that the difference of Sb and Sr in the modification and refinement of Mg2Si phase is significant. Addition of 0.4%Sb （mass fraction） to AZ61-0.7Si alloy can refine but not modify Mg2Si phase. Oppositely, by addition of 0.12%Sr to AZ61-0.7Si alloy, the Mg2Si phase changes from initial coarse Chinese script shape to fine granule and/or irregular polygonal shape. Accordingly, the St-modified AZ61-0.7Si alloy exhibits higher tensile and creep properties than the Sb-modified one. The difference of Sb and Sr in the modification and refinement of Mg2Si phase is possibly related to the following two aspects： 1） the disregistry at （100）A14Sr//（100）Mg2Si is lower than that at （0001）Mg3Sb2//（111）Mg2Si （0.69% vs 1.72%） and 2） the onset crystallizing temperature of the Sr-modified AZ61-0.7Si alloy is lower than that of the Sb-modified one （603.1 ℃ vs 606.9 ℃）.

关 键 词：MG2SI 镁合金 修改 SB 质量分数 蠕变性能 晶化温度 多边形 

分 类 号：TG146.22[一般工业技术—材料科学与工程]