用状态方程计算熔融态金属及其合金的密度

针对液体金属的特点,将变阱宽方阱链流体状态方程进行了简化。在将金属视为球状分子的前提下,简化后的状态方程包含3个分子参数:硬球直径、方阱阱深和对比阱宽。方程中硬球直径参数可直接采用金属原子本身的直径替代,方阱阱深和对比阱宽则可通过液态金属密度的实验数据回归得到。建立的两参数状态方程已被应用于包括熔融态碱金属、碱土金属、过渡金属等液态金属及其合金的密度计算中。结果表明,在较大的温度范围内,用简化的状态方程关联16种液态金属的密度,总的平均偏差为0.16%,结果令人满意,该方程还能预测高压下的密度。采用与温度无关的可调参数后,该方程能进一步计算合金在不同温度、压力和组成下的密度。

Calculating the Density of Molten Metals and Alloys Using an Equation of State

An equation of state(EOS) for square-well chain fluid with variable range(SWCF-VR) was simplified according to the characteristics of molten metals. If the metal is considered as a sphere, the simplified EOS contains three parameters, including hard sphere diameter, molecule interaction energy and reduced well width. Among them, the hard sphere diameter can be replaced by the metal atomic diameter, and the square-well depth and width can be obtained by the regression of experimental data of density of 16 different molten metals. This proposed two-parameter EOS was employed to the density calculation of alkali metals, alkaline earth metals, transient metals and their alloys. The results show that EOS can satisfactorily predict the density of 16 liquid metals in a wide range of temperatures as well as at a high pressure with a overall average deviation of 0.16%. Furthermore, EOS can satisfactorily predict the density of alloys at various temperatures, pressures and components using the binary interaction adjustable parameter independent of temperature.