Glass-forming ability and crystallization behavior of Ti-Cu-Ni-Sn-M (M=Zr, Mo, and Ta) metallic glasses

The kinetics of the glass transition and the crystallization behavior of Ti-Cu-Ni-Sn-M (M=Zr,Mo,Ta) glassy alloys were investigated by differential scanning calorimetry and x-ray diffraction. The glass-forming ability (GFA) of the glasses was analyzed in terms of the fragility concept and the width of the supercooled liquid region. The Ti-base glasses studied were found to have lower GFA than Zr, Pd, La, Fe, Mg-base bulk metallic glasses (BMGs), but to be comparative GFA to Ni- and Au-base BMGs. Higher Mo content or higher Ti-Ta content in the alloys lowers the GFA. The chemical complexity and multiphase crystallization requiring long-range atomic diffusion may contribute to the thermal stability of the supercooled liquid against crystallization. The products of crystallization of the glasses include bcc beta-Ti(M) solid solution and Ti2Ni and Ti2Cu intermetallics. (C) 2004 American Institute of Physics.