金属间化合物(Mg,Zn)_(12)Ce与(Mg,Zn)_(11)Ce的研究

对300℃时Mg-Zn-Ce系富镁侧化合物的成分特征、结构和相平衡关系进行了研究.结果表明,Mg-Zn-Ce富镁角存在一个Mg12Ce的二元置换固溶体(Mg,Zn)12Ce,还存在一个三元线性化合物(Mg,Zn)11Ce(τ相).(Mg,Zn)12Ce中Zn的范围为0~7.3%(原子分数),其晶体结构为体心四方晶格.三元线性化合物τ相含Zn为8.5%~43.5%(原子分数),其晶体结构为C底心正交晶格.(Mg,Zn)12Ce和τ相均与α(Mg)存在稳定的两相平衡,且在Mg-Zn-Ce系富镁角还存在三相平衡Mg+(Mg,Zn)12Ce+τ.

Study on the Intermetallics (Mg,Zn) 12 Ce and (Mg,Zn) 11 Ce

Phase composition，crystal structure and the relationship the phase equilibria in Mg-rich corner of Mg-Zn-Ce system at 300℃ were studied. The results showed that a substitution binary solid solution of Mg₁₂Ce identified as (Mg，Zn)₁₂Ce and a linear ternary compound identified as (Mg，Zn)₁₁Ce (τphase) were confirmed in Mg-rich corner of Mg-Zn-Ce system. The solid solubility of Zn in (Mg，Zn)₁₂Ce is about 0~7.3% (atomic fraction)， and the crystal structure of which is a body-centered tetragonal lattice structure. The Zn content of the linear ternaty compound τ phase is from 8.5% to 43.5% (atomic fraction)， and the crystal structure of it is a C-centered orthorhombic lattice. Both (Mg，Zn)₁₂Ce and τ phase were identified to be in two-phase equilibrim with α(Mg). A three-phase equilibrium of Mg+(Mg，Zn)₁₂Ce+τ in Mg-rich corner of Mg-Zn-Ce system was also identified.