Precipitation of icosahedral quasi crystalline phase in metallic Zr65Al7.5Ni5Cu17.5Re5 glass

Recently, the precipitation of an icosahedral quasicrystal line phase (I-phase) in metallic Zr65Al7.5Ni10Cu12.5M5 (M = Pd, Pt, Au and Ag) classes, which were obtained by adding noble metals to the well-known metallic Zr65Al7.5Ni10Cu17.5 glass, was reported. In the present work, the crystallization process of a metallic Zr65Al7.5Ni5Cu17.5Re5 glass, which was obtained by adding non-noble metal Re to Zr65Al7.5Ni10Cu17.5, was studied. Two exothermic peaks were observed in the differential scanning calorimetry curve of the metallic glass, of which the low temperature one corresponds to the precipitation of an I-phase. The present result demonstrates that the addition of Re is effective in promoting the precipitation of I-phase, in addition to the previously reported noble metals (Pd, Pt, An and Ag). The atomic radii of these elements are limited to the range of 0.137 to 0.144 nm, implying that atomic size is a significant factor. (C) 2001 Elsevier Science B.V. All rights reserved.