Wm. Husslage et al., Influence of reduction conditions on the expansion and microtexture of sintered hematite compacts during the transition to magnetite, MIN MET PR, 16(3), 1999, pp. 23-33
Permeability in the blast furnace shaft is adversely affected by low-temper
ature reduction degradation of sinters. The fundamental cause of this is th
e expansion of the iron oxide phase resulting from the reduction of hematit
e to magnetite. The present study shows that expansion behavior during the
hematite/magnetite reduction step and the resulting microstructure are stro
ngly influenced by the reduction temperature (partial oxygen pressure), the
reducing agent and the nature of the hematite. The reduction rate is of mi
nor importance. A reduction mechanism is proposed that can explain the dila
tion behavior and the magnetite microstructure. The results provide better
insight into the reduction degradation behavior.