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Indexed by:期刊论文

Date of Publication:2012-01-01

Journal:PHILOSOPHICAL MAGAZINE

Included Journals:SCIE、EI、Scopus

Volume:92

Issue:34

Page Number:4300-4319

ISSN No.:1478-6435

Key Words:clusters; cluster formula; alloy phases; structure; amorphous alloys

Abstract:Bulk metallic glasses are known to have a composition formula [cluster](glue atom)(1,3) within the framework of the cluster-plus-glue-atom model. The key issue in applying the cluster formula is the determination of the right clusters and glue atoms. As examples, alloy phases in the glass-forming systems Al-Ni-Zr and B-Co-Si are analysed from the viewpoint of nearest coordination polyhedral clusters. These alloy phases are described by [effective cluster](glue atom) x, where the effective cluster refers to true cluster composition after taking account of cluster-sharing in the phase structure. For each alloy phase, a principal cluster can be identified that features the local short-range order of that phase. It is pointed out that the principal clusters can express compositions with high glass-forming abilities, as verified by our experiments in Al-Ni-Zr and B-Co-Si-Ta.