Pd-Ni-P大块金属玻璃的形成及其转变动力学

FORMATION OF BULK METALLIC GLASS OF Pd-Ni-P AND TRANSFORMATION KINETICS

本文报道了Pd-Ni-P合金的过冷实验结果,研究了冷却速度对合金过冷行为的影响。通过将样品包裹在B_2O_3中从而减少样品的表面非均匀生核,使得样品在极低的冷却速度下形成大块金属玻璃。在玻璃转变温度(T_g=590K)处,冷却速度低达1K/s。利用经典的均匀生核与非均匀生核理论,计算了Pd_(40)Ni_(40)P_(20)合金的温度、时间转变曲线(即TTT图)。确定了合金的临界冷却速度。对结果进行了详细的讨论。

This paper reports the result of undercooling experiment of Pd-Ni-P alloy. Bulk metallic glass of Pd_(41)Ni_(40)P_(19) has been formed by thermal treatment with B_2O_3 as fluxing. The effect of cooling rate on the undercooling behavior was studie'd. The surface heterogeneous nuclea-tion was reduced by embeding the sample into B_2O3 melt. Thus the cooling rate used to form the glass was as low as 1 K/s at the glass transition temperature of 590 K. The temperature-time-transformation curves were calculated by using the classical homogeneous and heterogeneous nucleation theory. The critical cooling rates for the glass formation were calculated. The resuits are discussed in some detail.