Measurement of Equilibrium between Fe-Cr Alloys and CO-CO₂ Mixtures by Levitation Technique

Abstract

Investigations were made of the equilibrium between levitated droplets of Fe-Cr alloy (<18%Cr)and CO-CO₂ gas mixtures at a temperature range from 1 700 to 1 950°C and of the solubility product of chromium oxide in the melt at 1 800°C. Experimental results were discussed on the assumption that the values of e^C_C, e^O_C and e^O_O recommended by the 19th Committee of the Japan Society for the Promotion of Science are applicable in the present temperature range. The following conclusions are drawn :
log K₁(=log P_CO2/P_CO · a_o) =8 440/T-4.60
logK₂ (=log P²_CO/P_CO2·a_C) = -7870/T+ 6.90
logK₃ (= log P_CO/a_C · a_o) =570/T+ 2.30(17001950°C)
logK_Cr(=loga²_Cr·a³_O)=-1.376
e^Cr_O = -0.032
e^Cr_C= -0.018
e^Cr_Cr=0.002(1800°C)