Sn-16%Sb包晶合金的定向凝固组织演化研究  

Microstructures Evolution of Directionally Solidified Sn-16%Sb Hyperperitectic Alloy

作　　者：胡小武[1] 李双明[1] 刘林[1] 傅恒志[1] 

机构地区：[1]西北工业大学凝固技术国家重点试验室,陕西西安710072

出　　处：《铸造》2008年第5期446-450,共5页Foundry

基　　金：国家自然科学基金资助项目(50395100)

摘　　要：利用高温度梯度定向凝固装置对Sn-16wt.%Sb过包晶合金进行了试验研究,考察了不同凝固速度条件下获得的凝固组织、相的形貌及初生相体积分数的变化。结果表明,定向凝固组织为硬质初生金属间化合物SnSb相弥散分布于包晶β(Sn)相的软基体中,SnSb相呈四方形或三角形状,呈现小平面相生长形态。同时发现初生相随定向凝固速率增大而细化,分布更加均匀,其体积分数随定向凝固速率的增大先减小后增大。Directional solidified microstructures of Sn-16% Sb hyperperitectic alloy have been investigated at various solidification rates using a high-thermal gradient directional solidification apparatus. The results indicate that the solidification microstructures consist of hard primary intermetallic SnSb phase embedded in a matrix of soft peritectic β-Sn phase. The primary SnSb phase exhibits the faceted growth with the tetragonal or trigonal shapes. At the same time, the primary SnSb phase is refined with the increase of the solidification rate and dispersed more uniformly in the matrix of β-Sn phase. The volume fraction of SnSb phase firstly decrease and then increase, when the solidification rate increases in directional solidification of Sn-16% Sb hyperperitectic alloy.

关 键 词：Sn-16%Sb包晶合金 定向凝固 初生相 形态尺度 体积分数 

分 类 号：TG111.4[金属学及工艺—物理冶金]