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Indexed by:期刊论文

Date of Publication:2014-05-03

Journal:PHILOSOPHICAL MAGAZINE

Included Journals:SCIE、EI、Scopus

Volume:94

Issue:13

Page Number:1463-1477

ISSN No.:1478-6435

Key Words:cluster-plus-glue-atom model; quasicrystals; hardness

Abstract:In this paper, the hardness of ternary Al-based quasicrystals was assessed through an application of the cluster-plus-glue-atom model. In this model, any structure is decomposed into a first-neighbour strongly bonded cluster part and second-neighbour weakly bonded glue-atom part so that the overall structural information is condensed into a local structural unit [cluster](glue atom)(x). For quasicrystals, the averaged local units are formulated as [icosahedron] TM0,1(Transition Metal) and could be visualized as single icosahedron packing. Then, the hardness of quasicrystals was related to the rupture of weak inter-cluster bonds. Typically, theoretical hardness values of 8-9 GPa were obtained using 19 broken inter-cluster bonds, which accounts for about half of all the surface bonds of an icosahedron in the Mackay-type environment. The unit cluster formulas would act as rigid units during deformation and cracking.