| Abstract Scope |
The reduction of iron oxide with hydrogen is of importance for current and future decarbonized ironmaking. In some cases, the reduction rate of iron oxide pellets is influenced by the developing internal structure of the pellets - both porous and dense phases. Microstructural studies on pellets reduced in hydrogen at 1100 K will be presented. If the starting phase is magnetite, wuestite grows into the magnetite along preferred directions, as shown by electron backscattered diffraction, with no clear porosity formation. Upon reduction of the dense wuestite, iron tends to encapsulate the unreduced oxide, limiting the rate and extent of metallization. In contrast, if hematite is the starting phase, porosity forms during reduction to magnetite; this porosity is largely retained for reduction up to metallic iron. For the reduction of porous magnetite to wuestite, similar orientation relationships to those in dense wuestite appear to hold. |