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Icosahedral quasicrystals in Zn-T-Sc (T=Mn, Fe, Co, Ni) alloys

Ryo Maezawa·Shiro Kashimoto·Tsutomu Ishimasa
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Abstract

Starting from the Zn17Sc3 cubic approximant, new quasicrystal alloys were searched by replacement of Zn with transition elements, T. In the cases of T=Mn, Fe, Co and Ni, new icosahedral quasicrystals are formed in as-cast alloys as major phases at the alloy compositions of Zn75T10Sc15. All these quasicrystals belong to a primitive type, and have 6-dimensional lattice parameters, a6D, ranging from 7.044 to 7.107 A. They have the valence electron concentrations, e/a, ranging from 2.01 to 2.14, and almost the same ratios between the edge-length of the Penrose tile, aR, and the averaged atomic diameter d: aR/d~1.75. Moreover other Zn- and Cd-based quasicrystals including the same type of atomic cluster, Tsai-type cluster, also have the same values of e/a~2.1 and aR/d~1.75. The equality in e/a indicates that the Hume-Rothery mechanism plays an important role for the formation of these quasicrystals.

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Ryo Maezawa, Shiro Kashimoto, Tsutomu Ishimasa. 2003-08-25. Icosahedral quasicrystals in Zn-T-Sc (T=Mn, Fe, Co, Ni) alloys. https://doi.org/10.1080/09500830410001664544

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