Abstract: The phase diagram of ternary system YbCl₃-CaCl₂-LiCl has been determined by means of DTA. It was found that there are four surfaces corresponding to the primary crystallization of YbCl₃, CaCl₂, LiCl and Li₃YbCl₆ respectively and five univariant lines related to the secondary crystallization in this system. Temary eutectic point E(64.0% YbCl₃, 15.2%CaCl₂, 20.8%LiCl, 408℃) and ternary peritectic point P(55.2% YbCl₃, 20.2%CaCl₂, 24.6%LiCl, 448℃) were observed. The two equilibrium reactions with four phases occurred in this system are:
L=YbCl₃+Li₃YbCl₆+CaCl₂
L+LiCl=Li₃YbCl₆+CaCl₂

Key words: YbCl₃, YbCl₃-CaCl₂-LiCl system, phase diagram

摘要： 本文利用DTA研究了YbCl₃－CaCl₂－LiCL三元体系相图。发现该相图有对应于YbCL₃、CaCL₂、LiCL和Li₃YbCL₆的四个液相面，五条二次结晶线，一个三元低共熔点E(64.0%YbCL₃，15.2%CaCL₂, 20.8%LiCL，408℃)，一个三元转熔点P(55.2%YbCL₃，20.2%CaCL₂，24.6%LiCL，448℃）。相应的四相平衡反应为：
L＝YbCL₃＋YbCL6＋CaCL₂，
L＋LiCL＝Li₃YbCL₆＋CaCL₂。

关键词: YbCl₃, YbCl₃－CaCl₂-LiCl三元体系, 相图