摘要
The Co-Cr-W ternary system was critically assessed using the CALPHAD technique.The solution phases including the liquid,γ-Co,ε-Co and α-Cr were described by a substitutional solution model.The σ,μ and R phases were described by three-sublattice models of（Co,W）8（Cr,W）4（Co,Cr,W）18,（Co,Cr,W）7W2（Co,Cr,W）4 and（Co,W）27（Cr,W）14（Co,Cr,W）12,respectively,in order to reproduce their homogeneity ranges.A self-consistent set of thermodynamic parameters for each phase was derived.The calculated isothermal sections at 1 000,1 200 and 1 350 ℃ are in good agreement with the experimental data.A eutectoid reaction of R μ＋γ-Co＋σ in this ternary system was predicted to occur at 1 022 ℃.
用CALPHAD方法评估了Co-Cr-W三元系,计算了1000,1200和1350℃的相平衡。采用亚正规溶体模型描述了液相,fcc相,bcc相和hcp相。σ相,μ相,R相分别用模型(Co,W)8(Cr,W)4(Co,Cr,W)18,(Co,Cr,W)7W2(Co,Cr,W)4和(Co,W)27(Cr,W)14(Co,Cr,W)12来表示;得到了自洽的热力学相互作用参数。计算的1000,1200和1350℃的相图与实验数据吻合。
基金
Project(50771027)supported by the National Basic Research Program of China
Project(50771027)supported by the National Natural Science Foundation of China
