中文摘要：

利用第一性原理分子动力学模拟对Cu45Zr55-xAlx（x=3,7,12）块体非晶合金熔体在快速冷却为玻璃态过程中原子结构的演变进行了系统的研究.结果显示,以Al为中心的二十面体是合金熔体在液—固转变过程中最稳定的原子团簇结构,可视为该合金系中的基本结构单元;以Al为中心的稳定团簇的数量和在空间中的组成形式决定了该合金微观结构的非均匀性和原子扩散能力的大小,这也是影响合金宏观力学性能和玻璃形成能力的关键因素.

英文摘要：

Local structural changes from liquid to amorphous state in three Cu45Zr55-xAlx（x = 3, 7, 12） ternary metallic glasses have been investigated by the ab initio molecular dynamics simulation. The atomic structure of the glasses has been analyzed by means of bond-type index method in Honeycutt-Andersen and Voronoi tessellation method. Alcentered icosahedral clusters are identified as the basic local structural units and these Al-centered stable clusters play a key role in the structural heterogeneity and glass-forming ability of the Cu-Zr-Al bulk metallic glasses.