Statistical Thermodynamical Studies on Fundamental Reactions Concerning Steel-making. (2nd Report) II. Equilibrium between γ Iron and CO-CO₂ Gas Mixture

Abstract

It was pointed out that the chemical equation such as 3Fe+2CO\ ightleftarrowsFe₃C+CO₂ does not represent the essential features of this equilibrium.
We treated this problem on the basis of statistical thermodynamics apart from the above equation and determined the numerical values of the constants ΨFe_c, \varphi_cc and θ_c in the theoretical formula by comparing with the observation carried out recently by Smith, which represent the interaction energy between Fe ane C, the energy-contribution of C-C pair and the vibrational characteristic temperature of carbon respectively in the γ iron. Results obtained by this procedures are as follows. & Ψ_Fec=-135.98 Kcal
& \varphi_cc=8.35 Kcal  (at 1000°)
& θ^c/j_c=473°
It was shown, then, that the equilibrium properties of this system could be derived over the whole range of temperature and of gas compositions when these fundamental physical constants concerning the Fe-C interstitial solid solution were used.