Enthalpy relaxation of amorphous Fe76Mo7P17 Alloy upon Annealing
노태환Tae Hwan Noh, 강일구Il Koo Kang
Abstract
The enthalpy relaxation behaviour for amorphous Fe_75Mo_7P_17 alloy that has a clear glass transition phenomenon has been examined calorimetrically. Upon heating the sample annealed at temperature below T_g, an endothermic reaction occurs above T_a and the temperature evolving the ΔC_(p.max)(T_m) increases with lnt_a. The annealing temperature depen-dence of the magnitude of reversible endothermic reaction shows two distinct stages ; a low temperature one which is appeared at about T₃=550∼575k(∼T_g -l50K) and a high temperature one near T_g Moreover, the activation energy of enthalpy relaxation increases with T_m from 1.6 eV at T_m=580K to 2.6 eV at T_m = 700K. It was interpreted that the increase in activation energy with the rise of temperature is due to the transition from local rearrangement among metal atoms to long-mange rearrangement of metal and metalloid atoms.