Determination of thermodynamic properties in full composition range of Ti-Al binary melts based on atom and molecule coexistence theory

基于原子-分子共存理论的全浓度Ti-Al二元熔体热力学性质计算（英文）

The results of predicting thermodynamic properties in the full composition range of Ti-Al binary melts in a temperature range from 1973 to 2273 K were obtained by coupling with the developed thermodynamic model for calculating mass action concentration N_i of structural units in Ti-Al system based on the atom and molecule coexistence theory（AMCT）. Temperature dependence of the activity coefficients of Ti and Al in natural logarithmic form in the infinitely dilute solution（0x_（Ti）0.01） of Ti-Al binary melts was also determined from the calculated activity coefficients of Ti and Al at temperatures of 1973, 2073, 2173, and 2273 K. The standard molar Gibbs free energy change of dissolving pure liquid element i（l） for forming 1%（mass fraction） element i in Ti-Al binary melts further was deduced. With the aid of this model, meanwhile, the determined excess thermodynamic properties, such as the excess molar mixing Gibbs free energy/entropy/enthalpy were also calculated.

基于原子-分子共存理论建立计算温度为1973~2273 K及全浓度范围Ti-Al二元熔体质量作用浓度Ni的热力学模型。利用不同温度(1973、2073、2173和2273 K)下的模型计算结果,得到在无限稀溶液(0<x_(Ti)<0.01)中铝、钛活度因子的对数与温度的关系式。根据该表达式,进一步得到组元i溶解于Ti-Al二元熔体形成浓度为1%(质量分数)溶液为标准态的溶解Gibbs自由能。与此同时,对Ti-Al二元熔体的过剩Gibbs自由能、过剩熵、过剩焓也进行了计算。