NdCl_3－SrCl_2－MgCl_2三元体系相图的研究

Phase Diagram of Ternary System NdCl_3-SrCl_2-MgCl_2

借助于ＤＴＡ研究了ＮｄＣｌ３－ＳｒＣｌ２－ＭｇＣｌ２三元体系相图．发现体系内有对应于ＮｄＣｌ３、ＳｒＣｌ２、ＭｇＣｌ２和Ｓｒ３ＮｄＣｌ９的四个液相面、五条二次结晶线、一个三元低共熔点Ｅ（２７．０ｗｔ．％ＮｄＣｌ３．４２．５ｗｔ．％ＳｒＣｌ３，３０．５ｗｔ．％ＭｇＣｌ２；５２６℃）和三元转熔点Ｐ（２４．０ｗｔ．％ＮｄＣｌ３，４４．５ｗｔ．％ＳｒＣｌ２，３１．５ｗｔ．％ＭｇＣｌ２；５３２℃）．体系内有两个四相平衡反应为：ＡＬＮｄＣｌ３＋ＭｇＣｌ２＋Ｓｒ３ＮｄＣｌ９Ｌ＋ＳｒＣｌ２ＭｇＣｌ２＋Ｓｒ３ＮｄＣｌ９同时探讨了相图的若干规律。

AbstractThe phase diagram of ternary system NdCl3-SrCl2-MgCl2 has been investigated by means of DTA. Four surfaces corresponging to the primary crystallization of NdCl3, SrCl2,MgCl2 and Sr3NdCl9 respectively, five univariant lines related to the secondary crystallization,ternary eutectic point E(27.0 wt.% NdCl3, 42.5wt.% SrCl2, 30.5wt.% MgCl2; T. 526℃ ) and ternary peritectic point P(24.0wt.% NdCl3, 44.5wt.% SrCl2, 31.5wt.% MgCl2, T, 532℃ ) were found. The two reactions occurred in the system are:Some rules or phase diagram in the system RECl3-SrCl2-MgCl2 were also explored.