三元合金相图中的团簇线规律

Cluster line rule in ternary alloy phase diagrams

准晶、非晶等多组元合金具有很窄的成分区间,从原子团簇结构角度分析了这些相的结构特征,确定其成分规律.分析表明:无论是准晶、块体非晶,还是部分晶体合金相在内的金属间化合物都满足共同的团簇线规律,在三元相图中的三元相成分位于两条团簇线交点处,并且其中一条团簇线采用的团簇通常为密堆结构,因此,与传统晶体学完全不同.根据团簇线规则,三元相可以用"团簇+胶粘原子"的全新结构模型加以描述,该团簇线方法可以把微观结构的原子团簇与宏观相图有机地结合起来,构成合金相图的新特征.

Quasicrystals and metallic glasses with high glass forming abilities usually have narrow composition zones. The structural characteristics of the phases were analyzed from the viewpoint of atomic clusters, and the corresponding composition rule was determined. The analysis reveals that the intermetallic compounds including quasicrystals, bulk metallic glasses and some alloy phases satisfy a common cluster line rule. The composition of a ternary phase in ternary phase diagram is located at the intersection of two cluster lines, and one of them generally is a close packed cluster line, which is contrary to conventional crystallography. These ternary phases can be expressed with a new cluster-plus-glue atom model in accordance with the cluster line rule. The cluster line approach can constitute a bridge linking the atomic cluster to macro phase diagrams.