Change in local atomic environment during crystallization of Zr-based glassy alloys was studied by extended x-ray absorption fine structure (EXAFS) spectroscopy. The formation of icosahedral quasicrystalline phase followed by crystallization of tetragonal CuZr_(2) has been observed in the Zr_(70)Cu_(29)Pd_(1) glassy alloy during annealing up to 850 K. On the other hand, the binary Zr_(70)Cu_(30) alloy shows a single glassy to crystalline CuZr_(2) phase transformation. The local atomic environment of as-quenched Zr_(70)Cu_(30) alloy is matched to an icosahedral local atomic configuration, which is similar to that of the as-quenched Zr_(70)Cu_(29)Pd_(1) alloy and the alloy annealed at 593 K containing icosahedral phase. Considering that the supercooled liquid region appears prior to crystallization in the Zr_(70)Cu_(30) glassy alloy, the observed results support the theory claiming a strong correlation between the existence of local icosahedral short-range order and stability of the supercooled liquid state.
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