Heat capacity of Pd-Si, Ni-Si-B and Zr-based metallic glasses

The specific heat of metallic glasses containing Si and B (Ni78Si10B12 and Pd80Si20) and Zr-based metallic glasses(Zr60Al15Cu15Ni7.5Co2.5, Zr65Al17.5Cu7.5 and Zr67Cu33) was measured in the temperature range 77-800 K using an a.c. calorimeter. Several exothermic and endothermic processes were observed correspondingly to the transformation sequences for complete crystallization of all the glasses. The structural relaxation process appears with a decrease in heat capacity. For Ni-Si-B and Pd-Si glasses an abrupt increase in the specific heat is observed at the glass transition temperature T-g. For Zr-based glasses, however, a monotonous increase in the specific heat is observed just below T-g. Then the specific heat makes a peak and decrease abruptly with increasing temperature. The height of the peak increases with heating rate.