The influence of in situ spinel formation on microstructure and phase evolution of MgO–C refractories

The influence of in situ spinel formation on microstructure and strength of MgO–C refractories containing reactive alumina is investigated as a function of coking temperature. XRD, SEM, MOR techniques and rotary slag testing were employed to evaluate the microstructure and properties. The improvement of refractory properties was found to be related to the in situ spinel formation in the matrix. The microstructural evolution of the matrix was also influenced by the spinel formation from reactive alumina and MgO fine grains. It was also clarified that the spinel stoichiometric was varied from normal type to alumina rich depending upon the firing temperature and atmosphere.