新型Mg-Gd-Y合金富镁角的相图计算及实验测定  

Calphad and Experimental Study on the New Type Mg-Gd-Y Phase Diagram in the Mg-Rich Region

作　　者：赵娟[1] 李建平[1] 郭永春[1] 杨忠[1] 杨觉明[1] 梁民宪[1] 

机构地区：[1]西安工业大学,陕西西安710032

出　　处：《稀有金属材料与工程》2008年第2期281-285,共5页Rare Metal Materials and Engineering

基　　金：国家重大基础研究发展规划资助项目(513300114A)

摘　　要：用相图计算软件Pandat计算了Mg-Gd-Y合金的液相面投影图、室温(25℃)的等温截面图、Mg-xGd-2Y和Mg-xGd-7Y合金系的垂直截面图,并选取了Mg-5Gd-2Y和Mg-1Gd-7Y两种合金,通过相图计算与实验验证相结合的方法对合金的相平衡及凝固过程进行了研究。用光学显微镜、扫描电镜、能谱仪及示差扫描量热仪对该合金的室温平衡相组成及凝固过程的相变温度点进行了验证。结果表明,相平衡热力学计算结果与实验结果吻合,Mg-5Gd-2Y合金的凝固顺序为L—L+α-Mg—α-Mg+Mg5Gd—α-Mg+Mg24Y5+Mg5Gd;Mg-1Gd-7Y合金的凝固顺序为L—L+α-Mg—α-Mg+Mg24Y5—α-Mg+Mg24Y5+Mg5Gd,两合金的室温平衡组织均为α-Mg+Mg24Y5+Mg5Gd。The phase diagram of Mg-Gd-Y system alloys of Mg-rich cornel was calculated using Calphad software Pandat and the phase equilibria and solidification sequences of the alloys Mg-5Gd-2Y and Mg-1Gd-7Y were compared with the experimental results of OM, SEM-EDX analysis and DSC spectrum. The results show that the thermodynamic alloy calculated results of phase equilibria agree well with the experimental results. Although as cast equilibria microstructure of the two alloys at room temperature consist of α-Mg＋ Mg24Y5＋Mg5Gd, the solidification sequences of them are quite different. The solidification sequence of the alloy Mg-5Gd-2Y is as following： L-L＋Mg-Mg＋Mg5Gd-Mg＋Mg24Y5＋Mg5Gd and the alloy Mg-1Gd-7Y is as following： L-L＋Mg-Mg＋Mg24Y5-Mg＋ Mg24Y5＋Mg5Gd.

关 键 词：相图计算 Pandat软件 Mg-Gd-Y相图 Mg-5Gd-2Y Mg-1Gd-7Y 

分 类 号：TG146.22[一般工业技术—材料科学与工程]