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借助于ＤＴＡ与Ｘ射线衍时法研究了ＤｙＣｌ＿３一ＭＣｌ＿ｎ（Ｍ＝Ｌｉ、Ｍｇ、Ｃａ、Ｐｂ；ｎ＝１或２）二元体系相图。发现ＤｙＣｌ＿－ＬｉＣｌ体系有一固液异组成化合物Ｌｉ＿３ＤｙＣｌ＿６生成，在４７０℃有一相转变。相图属固液异组成相图类型，其无变点分别为ｐ（４７０ｍｏｌ％ＤｙＣｌ＿３，４７５℃），ｅ（５１．５ｍｏｌ％ＤｙＣｌ＿３，４４８℃）；而ＤｙＣｌ＿３一ＭｇＣｌ＿２，ＣａＣｌ＿２，ＰｂＣｌ＿２体系都属简单低共熔型相图。其低共熔点ｅ的组成与温度分别为：６５．１ｍｏｌ％ＤｙＣｌ＿３（５９３℃）、６１．１ｍｏｌ％ＤｙＣｌ＿３（５４６℃）和３２．９ｍｏｌ％ＤｙＣｌ＿３（４３２℃）。同时在固相下都有不稳定化合物生成，其化合物分别为：Ｍｇ＿２ＤｙＣｌ＿７、ＣａＤｙ＿２Ｃｌ＿８和ＰｂＤｙＣｌ＿５。它们的分解温度分别为５５５、４９５和４２３℃（在３９９℃有一相转变）。同时探讨了相图的某些规律。
The phase diagram of DyCl3-MCl_n (M = Li, Mg, Ca, Pb; n = 1 or 2) binary system was studied by means of DTA and X-ray diffraction. It is found that the DyCl_-LiCl system has a solid-liquid heterostructured compound Li_3DyCl_6, which has a phase transition at 470 ℃. The phase diagrams belong to the heterogeneous phase diagram of solid-liquid heterogeneous system, and their non-changeable points are p (470mol% DyCl_3,475 ° C) and e (51.5mol% DyCl_3,448 ° C) respectively, while DyCl_3-MgCl_2, CaCl_2 and PbCl_2 systems belong Simple eutectic phase diagram. The composition and temperature of its eutectic point e are: 65.1 mol% DyCl_3 (593 ° C), 61.1 mol% DyCl_3 (546 ° C) and 32.9 mol% DyCl_3 (432 ° C). At the same time, both of them have unstable compounds in the solid phase, and their compounds are Mg2DyCl7, CaDy2Cl8 and PbDyCl5, respectively. Their decomposition temperatures are 555, 495 and 423 ° C (one phase transformation at 399 ° C). Also discussed some of the laws of the phase diagram.