Al-Si-Fe合金熔体质量作用浓度的热力学模型

Thermodynamic model for calculating mass action concentration of Al-Si-Fe alloy melts

基于原子分子共存理论(AMCT)建立了计算Al-Si二元熔体及Al-Si-Fe三元熔体结构单元质量作用浓度的热力学模型。针对Al-Si二元系熔体,根据FactSage热力学软件计算的活度得到生成复杂分子Al2Si和AlSi的反应的标准摩尔吉布斯自由能的表达式,进而获得了Al-Si二元熔体中标准摩尔溶解吉布斯能变的表达式。同时建立了Al-Si-Fe三元系熔体的质量作用浓度计算模型,并与文献报道的结果对比。结果表明:1673~1873 K下在全浓度范围内计算得到的Al-Si和Al-Si-Fe熔体的质量作用浓度与前人报道的数据吻合良好。

A thermodynamic model for calculating the mass action concentration of structural units in Al-Si binary melts and Al-Si-Fe ternary melts was established based on the atom and molecule coexistence theory(AMCT).The expression of standard molar Gibbs free energy for the reactions of forming complex molecules,such as Al2Si and AlSi,in the Al-Si binary system melts were obtained by using the activities calculated by the FactSage software,and then the change of standard molar dissolved Gibbs free energy in Al-Si binary melts was also acquired.At the same time,the calculation model of the mass action concentration of Al-Si-Fe ternary system melts was developed and compared with the results reported in the relative literatures.The results show that the calculated mass action concentration of structural units in the full concentration range of Al-Si and Al-Si-Fe melts at the temperature range from 1673 to 1873 K were consistent with the data reported by previous researchers.