根据分子动力学理论建立了液态ZA2 7合金的原子集团 ,结合计算机编程构造出ZA2 7合金α相与液相共存时的原子构形及α相大角度重位点阵晶界模型 .利用递归法计算了铁、稀土元素固溶于晶粒内 ,游离于固液相界面及其在α相晶界处的环境敏感镶嵌能 ,计算了铁、稀土元素与Al的键级积分 .由此得出 :铁、稀土处于固液相界区比在晶内更稳定 ,解释了铁、稀土在α相内溶解度很小 ,结晶时富集于固液相界前沿液体中 ,从而导致凝固结束后铁、稀土元素偏聚于晶界 ,并形成成分复杂的稀土化合物的事实 According to the theory of molecular dynamics, an atomic group of liquid ZA2 7 alloy was established, and the atomic configuration and α-phase large-angle heavy-point lattice boundary model of α-phase and liquid phase of ZA2 7 alloy were constructed by computer programming. Calculated iron and rare earth elements in the grain, dissociation in the solid-liquid interface and the α-phase grain boundary environment-sensitive mosaic energy, calculated the iron, rare earth elements and Al bond-level integration. : Iron, rare earth in the solid-liquid boundary more stable than in the crystal, explained the iron, rare earth in the α phase solubility is very small, crystallization enrichment in the liquid front of the solid-liquid boundary, resulting in solidification after the end of iron, The fact that rare earth elements are segregated at grain boundaries and form rare earth compounds with complex compositions