中文摘要：

基于原子和分子共存理论建立计算Al-Ti二元合金系结构单元质量作用浓度的热力学模型.利用文献报道的2073、2173和2273 K下Al-Ti二元系的活度计算了生成Al3Ti、Al Ti和Al11Ti5反应的平衡常数,并进一步得到其标准摩尔吉布斯自由能的表达式.使用文献报道的不同温度下Al-Ti二元合金系全浓度范围内组元Al和Ti的活度aAl和aTi与原子和分子共存理论定义的质量作用浓度NAl和NTi进行比较.结果表明：在Al-Ti二元合金熔体全浓度范围内计算得到的质量作用浓度NAl和NTi与文献报道的活度符合很好.同时,计算得到的Al-Ti二元合金系中结构单元Al3Ti和Al11Ti5的平衡物质的量与其质量作用浓度的关系呈＂棒状＂,而结构单元Al Ti的平衡物质的量与其质量作用浓度的关系呈＂纺锤＂形.

英文摘要：

A thermodynamic model is proposed for calculating the mass action concentration of structural units in the Al-Ti binary melt system based on the atom-molecule coexistence theory. The standard equilibrium constants of reactions for forming three associated molecules as Al3 Ti,Al Ti,and Al11Ti5 in the Al-Ti binary melt system at the temperature of 2073 to 2273 K are calculated based on the activity reported in the literature,and the expressions of the standard molar Gibbs free energy change of reactions are obtained.Meanwhile,the calculated mass action concentrations NAl and NTiof Al and Ti are compared with the reported activities of both Al and Ti in the full composition range of the Al-Ti binary melt system at different temperatures from the literature. The results show that the calculated mass action concentrations NAland NTiare in agreement with the activities aAland aTiin the reported literature. The relationship between the calculated mass action concentration Niand the calculated equilibrium amount of substance niof Al3 Ti and Al11Ti5 in the Al- Ti binary melt system is rod-type. However,the relationship between the calculated mass action concertation NAl Tiand the calculated equilibrium amount of substance nAl Tiin this binary melt system is spindle-type.