1 Collaborative Innovation Center of Steel Technology, University of Science and Technology Beijing, Beijing 100083, China; 2 School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
High-performance chromite by structure stabilization treatment
1 Collaborative Innovation Center of Steel Technology, University of Science and Technology Beijing, Beijing 100083, China; 2 School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
摘要 Chromite is an important raw material applied in refractories. Efforts have been made to obtain high-performance chromite by adding MgO and Al2O3 from the viewpoint of structure optimization. In order to explore the effect of Al2O3 and MgO on the structure, two formulas, i.e., Mg-rich and Al-rich ones, were selected. The phase and microstructure development of samples heated in the temperature range of 1200–1600 °C were studied by X-ray diffraction and scanning electron microscopy with energy-dispersive spectrometry. MgO and Al2O3 added have diffused into chromite successfully by heat treatment. MgO diffuses into chromite, occupying the tetrahedral vacancies caused by the diffusion and oxidation of Fe2+ ions to stabilize the structure. Al2O3 diffuses into the surface layer of chromite, forming spinel-sesquioxide structure. Al-rich sample which has spinel-sesquioxide structure shows better corrosion resistance toward fayalite slag than Mg-rich sample which has single spinel structure by blocking the interdiffusion between Fe2+ ions in fayalite slag and Mg2+ ions in chromite.
Abstract：Chromite is an important raw material applied in refractories. Efforts have been made to obtain high-performance chromite by adding MgO and Al2O3 from the viewpoint of structure optimization. In order to explore the effect of Al2O3 and MgO on the structure, two formulas, i.e., Mg-rich and Al-rich ones, were selected. The phase and microstructure development of samples heated in the temperature range of 1200–1600 °C were studied by X-ray diffraction and scanning electron microscopy with energy-dispersive spectrometry. MgO and Al2O3 added have diffused into chromite successfully by heat treatment. MgO diffuses into chromite, occupying the tetrahedral vacancies caused by the diffusion and oxidation of Fe2+ ions to stabilize the structure. Al2O3 diffuses into the surface layer of chromite, forming spinel-sesquioxide structure. Al-rich sample which has spinel-sesquioxide structure shows better corrosion resistance toward fayalite slag than Mg-rich sample which has single spinel structure by blocking the interdiffusion between Fe2+ ions in fayalite slag and Mg2+ ions in chromite.
En-hui Wang,Chang Luo,Jun-hong Chen, et al. High-performance chromite by structure stabilization treatment[J]. Journal of Iron and Steel Research International, 2020, 27(2): 169-179.
2020, Vol. 27 
