Structure of Metallic Iron Formed in Iron Ores by CO–H<sub>2</sub> Reduction

To improve the stability of hydrogen-enriched reduction operations in blast furnaces, it is necessary to maintain gas permeability in the cohesive zone. The reduced and produced metallic iron phases contribute to the strength of the iron ore in the cohesive zone. However, the form of the iron produced and its evaluation method have not been established. In this study, sinters, pellets, and lump ores were reduced, and the iron phase produced was evaluated using a local thickness measurement method. The effects of the reduction conditions and the composition of the iron ore on the local thickness profiles of the iron structures in the ore were discussed.