Ti Deoxidation Equilibrium in Molten Fe–Ni Alloys at Temperatures between 1823 to 1923 K

Abstract

Equilibrium relation between Ti and O in molten Fe–Ni alloy has been investigated at 1873 to 1923 K. Ti oxide equilibrated with molten Fe–Ni alloy has been determined by EBSD (Electron Backscatter Diffraction) pattern analysis using FE-SEM (Field Emission Scanning Electron Microscope). The present results have been numerically analyzed by the excess Gibbs free energy change of mixing for the Fe–Ni–Ti–O system with Redlich–Kister type polynomial. Redlich–Kister type polynomial parameters concerning Ni and Ti were determined as follows,
⁰Ω_Ni–Ti = 424280−270.40T J/mol (X_Ti<0.003, 1823 K≤T≤1923 K),
¹Ω_Ni–Ti = −663380+313.15T J/mol (X_Ti<0.003, 1823 K≤T≤1923 K).