采用电磁悬浮落滴式量热方法测定了液态三元Ni60Cu20Fe20合金在1436—2008K温度范围内的比热,实验获得的最大过冷度达232K(0.14TL),结果表明比热值为33.27J.mol-1.K-1,并且随温度变化很小.在实验基础上,根据分子动力学方法结合嵌入原子势(EAM)和Quantum Sutton-Chen多体势(QSC)对比热进行了理论计算,揭示了其在1200—2500K范围内随温度的变化关系,两种势函数的模拟计算结果均随温度降低而缓慢升高.将两种模型计算出的比热与实验结果比较,发现QSC模型比EAM模型更适合计算液态Ni60Cu20Fe20合金比热.
The specific heat of liquid Ni60Cu20Fe20 ternary alloy was measured by electromagnetic levitation drop calorimetry in the temperature range from 1436 to 2008K.The maximum undercooling achieved in experiment is 232K(0.14TL).The specific heat was determined as 33.27J·mol^-1 ·K^-1 which varied slightly with temperature.Furthermore,the temperature dependence of the specific heat of normal and undercooled liquid Ni60Cu20Fe20 alloy was calculated by molecular dynamics method with embedded-atom potential(EAM) and quantum Sutton-Chen many-body potential(QSC).The calculated results indicate that the specific heat increases slowly with the decrease of temperature.By comparing these theoretical calculations with experiments,we found that the QSC model is more reasonable for predicting the specific heat of liquid Ni60Cu20Fe20 alloy than the EAM model.