| The crystallization of mechanically alloyed Zr67Ti6.14Nb1.92Cu10.67Ni8.52Al5.75 glassy powder is investigated by time-resolved X-ray diffraction. The powder displays a multi-step crystallization behavior characterized by the formation of a metastable nanoscale quasicrystalline phase during the first stage of the crystallization process. At higher temperatures, coinciding with the second crystallization event, the amorphous-to-quasicrystalline transformation is followed by the precipitation of the tetragonal Zr2Cu phase (space group I4/mmm) and the tetragonal Zr2Ni phase (space group I4 /mcm). The transformations are gradual and the quasicrystals and the subsequent phases coexist over a temperature interval of about 25K. |
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