Evidence of polymorphous amorphous-to-quasicrystalline phase transformation in Zr66.7Pd33.3 metallic glass

The amorphous-to-quasicrystalline phase transformation and the pressure effect on the transformation in a Zr66.7Pd33.3 metallic glass have been investigated by in situ x-ray diffraction measurements using synchrotron radiation. It is found that the transformation is a polymorphous reaction and external pressure enhances the onset temperature for the formation of quasicrystals with a rate of 22 K/GPa while the temperature interval for the stability of quasicrystals remains almost unchanged in the pressure range of 0-4 GPa. The enhancement of the onset temperature for the formation of quasicrystals has been further discussed with the nucleation theory. (C) 2002 American Institute of Physics.