Thermal stability and fragility of Pd-Si binary bulk metallic glasses

The thermal stability of the glassy structure and the supercooled liquids of Pd80+xSi20-x (x = 0, 1, and 2) binary bulk metallic glasses were investigated by differential scanning calorimetry. It is found that Pd-Si binary metallic glasses exhibit large activation energy for glass transition and crystallization, indicating the glassy structure and the supercooled liquids possess high thermal stability. Based on the kinetic nature of the glass transition and thus the resulted heating rate dependence, the fragility index of the Pd-Si binary glassy alloys has been obtained, and compared with other bulk metallic glasses. (C) 2010 Elsevier B.V. All rights reserved.