Ti-Al-Nb三元系中α/β及α/γ相平衡的热力学计算  

THERMODYNAMIC CALCULATION OF THE α/β ANDα/γPHASE EQUILIBRIA IN THE Ti-Al-Nb TERNARY SYSTEM

作　　者：李俊涛[1] 蒋敏[2] 郝士明[2] 李世琼[1] 仲增墉[1] 

机构地区：[1]钢铁研究总院高温材料研究所,北京100081 [2]东北大学材料科学与工程系,沈阳110004

出　　处：《金属学报》2001年第10期1064-1068,共5页Acta Metallurgica Sinica

基　　金：国家自然科学基金59371025

摘　　要：对三元系不同结构相平衡进行了巨势法分析，确定了三元系不同结构相平衡的巨势法计算方法．采用亚正规溶体模型描述Ｔｉ－Ａｌ－Ｎｂ三元系中α，β和γ相的Ｇｉｂｂｓ自由能，由Ｔｉ－Ａｌ，Ａｌ－Ｎｂ和Ｎｂ－Ｔｉ二元系及Ｔｉ－Ａｌ－Ｎｂ三元系相平衡数据，计算了相互作用参数ＩαＡＩＮｂ，ＩαＮｂＴｉ；ＩβＴｉＡｌ，ＩβＮｂＴｉ，ＩβＮｂＴｉ，ＩγＴｉＡｌ，ＩγＡｌＮｂ，和ＩγＮｂＴｉ.利用获得的热力学参数，运用巨势法对Ｔｉ－Ａｌ－Ｎｂ三元系１４２３－１６７３ Ｋ范围内α／β及 α／γ相平衡进行了计算．计算结果与实测相图吻合得很好，证明本方法是可行的，获得的相互作用参数值是合理的．The dissimilar phase equilibrium in ternary system was analyzed by grand potential method. Based on this analysis, the grand potential approach for calculating the dissimilar phase equilibrium in the ternary system was proposed. The Gibbs free energies of the α, β and γ phases in the Ti-Al-Nb ternary system were described by subregular solution model. The interaction parameters, IαAlNb, IαNbTi, IβTiAl, IβAlNb, IβNbTi, IγTiAl, IγAlNb and IγNbTi were calculated by the experimental data in the Ti-Al, Al-Nb, Nb-Ti binary systems and the Ti-Al-Nb ternary system. Using the obtained thermodynamic parameters, the α/β and the α/γ phase equilibria in Ti-Al-Nb ternary system at 1423 and 1673 K were calculated by the grand potential approach. The calculated results are cosistant well with the experimental phase diagrams, which shows that the grand potential approach is feasible and the interaction parameters obtained in this present work are correct.

关 键 词：相平衡 巨势法 热力学计算 钛合金 

分 类 号：TG146.23[一般工业技术—材料科学与工程]