(冶金工业部钢铁研究总院, 北京100081)
摘 要: 利用C-CO控制反应2[Y]+3CO=Y2O3+3C的平衡氧位,使多孔石墨坩埚中[Y]达到等活度的原理,结合解病态方程组的共轭斜量法,求解出1200 ℃铜液中Y与Sn、Zn、Pb的活度相互作用系数,得到了反应2[O]+2[Y]=Y2O3的平衡常数K=3.3×1019,铜液中Y2O3的吉氏标准反应自由能为-550.53 kJ/mol。
关键字: 等活度法 活度相互作用系数 Cu-Y-Sn,Cu-Y-Zn, C u-Y-Pb吉氏标准反应自由能
(Central Iron and Steel Research Institute, Ministry of Metallurgical Industry, Beijing 100081)
Abstract:The isoactivity of [Y] of samples was obtained in multiple-hole graphite crucibles by controlling the oxygen potential through the reaction 2[Y]+3CO=Y2O3+3C. The activity interaction coefficients between Y and Sn, Zn, Pb alloying elements were determined as follows by using conjugate gradient method of solving ill-conditioned equations: for the Cu-Y-Sn sysytem, eYSn=1.544, γYSn=-0.280, γYSn,Y=-1.005, eSnY=2.060, γSnY=-1.528, εSnY=εYSn=662.5; for the Cu-Y-Zn system, eYZn=0.062, γYZn=-0.445, γYZn,Y=0.169, eZnY=0.047, γZnY=0.142, εYZn=εZnY=14.7, for the Cu-Y-Pb system, eYPb=-0.183, γYPb=-0.100, γYPb,Y=0.119, ePbY=-0.432, γPbY=0.315, εPbY=εYPb=-139.5, the equilibrium products for Cu-Y-M (M=Sn, Zn, Pb) systems were identified as Y2O3 at 1200℃. The equilibrium constant of reaction 3[O]+2[Y]=Y2O3 is 3.3×1019, the standard free energy of formation of Y2O3 in liquid Cu is -550.53 kJ/mol.
Key words: isoactivity activity interaction coefficient Cu-Y-Sn, Cu-Y-Zn, Cu-Y-Pb