(1. 重庆工学院 材料科学与工程学院，重庆400050；2. 重庆大学 材料科学与工程学院，重庆400030)
摘 要: 通过金相、扫描电镜(SEM)、X射线衍射分析(XRD)和差热分析(DSC)等手段，研究Sb变质对Mg-6Al-1Zn-0.7Si镁合金热处理组织和力学性能的影响，尤其是对合金固溶处理组织的影响。结果表明：固溶处理可以变质Mg-6Al-1Zn-0.7Si镁合金铸态组织中的汉字状Mg2Si相，使Mg2Si相从汉字状变为短杆状和条块状，并且添加0.4%Sb到实验合金中可使固溶处理变质汉字状Mg2Si相的效果提高。也正是由于固溶处理可以使实验合金组织中的汉字状Mg2Si相变质，使得Mg-6A1-1Zn-0.7Si合金时效处理后获得了较铸态更高的的抗拉性能和抗蠕变性能，并且添加0.4%Sb可以进一步增强热处理对性能的改善作用。
关键字: Mg-A1-Si系合金；Mg-6A1-1Zn-0.7Si合金；Sb；固溶处理；Mg2Si相
（1. Materials Science and Engineering College, Chongqing Institute of Technology,Chongqing 400050, China;2. Materials Science and Engineering College, Chongqing University,Chongqing 400030, China）
Abstract:The effects of Sb modification on the heat-treated microstructure and mechanical properties of Mg-6A1-1Zn-0.7Si alloy, especially on the solutionized microstructure, were investigated by means of metallurgical phase analysis, scanning electron microscopy (SEM) analysis, X-ray diffraction (XRD) analysis, and differential scanning calorimetry (DSC) analysis. The research results indicate that after being solutionized, the Chinese script shaped Mg2Si phases in the microstructure of the alloy are modified, namely, their morphologies change from Chinese script shape to short pole and block shapes, and the higher modification efficiency could be obtained for the alloy added 0.4%Sb. The effect of solid solution treatment on the morphology of Chinese script shaped Mg2Si phases, results in higher tensile and creep properties for the experimental alloy followed by aging treatment, and the properties improvement resulted from heat treatment, is more obvious for the alloy added 0.4%Sb.
Key words: Mg-A1-Si based alloy; Mg-6A1-1Zn-0.7Si alloy; Sb; solid solution-treatment; Mg2Si phase
