Article ID: ISIJINT-2020-672
The evolution of inclusions with Ce addition and Ca treatment in Al-killed steel during RH refining process was investigated through experimental observations and thermodynamic calculations. The results indicated that the typical inclusions before Ce addition are CaO–Al2O3 inclusions, which were a liquid state during RH refining. After Ce addition, the typical inclusions was transformed from calcium aluminate inclusion to (Ca–Ce–S–O)+(Ce–Al–Ca–O) complex inclusion. After Ca treatment, the types and morphologies of typical inclusions in steel did not change. Experimental observation and thermodynamic calculations shown that a certain amount of Ca addition can't affect the formation of Ce-containing inclusion, which may indicate that Ca treatment should not be carried out for rare earth treated steel.