用改良静滴法对钼浓度在0%到10%(质量分数)的NiCoAlMo四元合金的液态密度进行了测量,NiCoAlMo合金的Ni:Co:Al摩尔比与商用镍基超合金TMS75、INCO713、CM247LC和CMSX-4的Ni:Co:Al摩尔比接近(xNi:xCo:xAl=73:12:15)。结果表明:液态密度随温度的增加而减小,随合金中钼浓度的增加而增加;液态NiCoAlMo四元合金的摩尔体积随温度和合金中钼浓度的增加而增加,与理想混合相比,呈负偏差。由镍基二元合金中镍、钴、铝、钼4个元素的偏摩尔体积计算获得的NiCoAlMo四元合金的液态密度与实验测量密度吻合良好,表明在误差范围内,多元镍基合金的液态密度可以通过二元镍基合金中相应元素的偏摩尔体积进行预测估计。
The density of liquid NiCoAlMo quaternary alloy with a fixed molar ratio of Ni:Co:Al(xNi:xCo:xAl≈73:12:15) which is close to the average value of the commercial Ni-based superalloys TMS75,INCO713,CM247LC and CMSX-4,and molybdenum concentration change from 0% to 10%(mass fraction) was measured by a modified sessile drop method.It is found that the density of the liquid NiCoAlMo quaternary alloy decreases with increasing of temperature,but increases with the increase of molybdenum concentration in the alloys.The molar volume of liquid NiCoAlMo quaternary alloy increases with the increase of temperature and molybdenum concentration,and shows a negative deviation from the ideal linear mixing.The liquid density of NiCoAlMo quaternary alloy calculated from the partial molar volumes of nickel,cobalt,aluminum and molybdenum in the corresponding Ni-bases binary alloy are in good agreement with the experimental results;it means that within the error tolerance range the density of liquid Ni-based multi-component alloys can be predicted from the partial volumes of elements in Ni-based binary alloys in liquid state.