A structural model for metallic glasses
A structural model for metallic glasses
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DOI：
10.1017/s1431927604885866
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发表时间：
2004-08
期刊：
影响因子：
41.2
通讯作者：
D. Miracle
中科院分区：
文献类型：
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作者：
D. Miracle
尽管人们对金属玻璃的各种工程应用有着浓厚的兴趣，但其结构的许多细节仍然是一个谜。在这里，我们提出了第一个引人注目的金属玻璃原子结构模型。该结构模型是基于一种新的球形堆积方案——原子团簇的密集堆积。溶剂原子的随机定位和溶质原子的中等范围原子顺序相结合，在高达1 nm的径向距离上成功地再现了衍射数据。虽然金属玻璃可以具有任意数量的化学上不同的溶质，但该模型表明，它们含有不超过三种拓扑上不同的溶质，并且这些溶质相对于溶剂原子具有特定的和可预测的尺寸。最后，该模型包含缺陷，为金属玻璃的结构描述提供了丰富性。该模型准确地预测了典型溶剂原子的第一配位壳中溶质原子的数目，并为广泛的简单和复杂合金提供了准确预测金属玻璃成分的卓越能力。
Despite the intense interest in metallic glasses for a variety of engineering applications, many details of their structure remain a mystery. Here, we present the first compelling atomic structural model for metallic glasses. This structural model is based on a new sphere-packing scheme—the dense packing of atomic clusters. Random positioning of solvent atoms and medium-range atomic order of solute atoms are combined to reproduce diffraction data successfully over radial distances up to ∼1 nm. Although metallic glasses can have any number of chemically distinct solute species, this model shows that they contain no more than three topologically distinct solutes and that these solutes have specific and predictable sizes relative to the solvent atoms. Finally, this model includes defects that provide richness to the structural description of metallic glasses. The model accurately predicts the number of solute atoms in the first coordination shell of a typical solvent atom, and provides a remarkable ability to predict metallic-glass compositions accurately for a wide range of simple and complex alloys.