Reduction mechanism of iron-manganese oxide with carbon was investigat
ed by an effluent gas analysis method. The reaction between carbide fo
rmed in this process and the oxide was also studied. EPMA and X-ray di
ffraction examinations showed the presence of M(3)C phase in the reduc
tion products. Effluent gas analysis method was useful and troubleless
for studying such reduction process under high temperature and high v
apor pressure conditions and also for extremely refractory-attaking ma
terials.