Heat of evolution and structural analysis on the non-Newtonian viscous flow of Pd40Ni40P20 glassy alloy
15 July 2004
The evolution of specific heat of a Pd40Ni40P20 glassy alloy subjected to different degrees of non-Newtonian flow condition near the glass transition temperature, T-g, was investigated by a differential scanning calorimetry (DSC) method. Three exothermic relaxation spectrums were observed in temperature dependence of the specific heat. One of the relaxations in T > 490 K (= T-g - 95 K) strongly depended on the flow condition, on the other hand, the others did weakly. This relaxation has previously been reported to be due to the long-range disordering between metal and metalloid constituents. The local atomic structure causing the non-Newtonian flow is therefore expected to show modification among metal and metalloid elements. Using a X-ray diffraction method followed radial distribution function analysis, this modification is observed. (C) 2003 Elsevier B.V. All rights reserved.