Release Time:2019-03-09  Hits:

Indexed by: Journal Papers

Date of Publication: 2015-12-15

Journal: JOURNAL OF ALLOYS AND COMPOUNDS

Included Journals: Scopus、EI、SCIE

Volume: 652

Page Number: 63-69

ISSN: 0925-8388

Key Words: Solid solution; Body-centered-cubic metals; Cluster-plus-glue-atom model; Cluster formula; Industrial alloy compositions

Abstract: The structures of solid solution alloys are characterized by chemical short-range orders that determine largely the alloy performance. In the present work, the cluster-plus-glue-atom model, which suits for the description of chemical short-range orders in solid solutions, is introduced in the structural description of BCC solid solutions. In this model, solute atoms form 1st-neighbor clusters in the solvent matrix, so that a stable solid solution is represented by a specific local unit containing the characteristic cluster plus certain number of outer-shell 2nd neighbor glue atoms, or expressed in cluster formula [cluster](glue atom)(x). The cluster packing geometry is then analyzed and their structural stability is discussed in terms of cluster packing density. The cluster packing density reaches the maximum when x = 1, signifying that these alloys might possess special stabilities and henceforth good properties. Commonly-used BCC alloys in Zr-, Ti-, V-, Nb-, Ta-, Mo-, W-, and U-based systems are found to conform to the as-mentioned composition formulas, and in particular to that with x = 1, thus unveiling universal composition rules for BCC metals. (C) 2015 Elsevier B.V. All rights reserved.