Volume Stability of Spinel-Bonded Magnesia Castables

摘要

Volume stability and structure spalling resistance are still the 2 major drawbacks to insure full commercialization of periclase-based castables for steelmaking applications. Rsults of a systematic study on the thermal expansion behavior of magnesia-based castables, with hydratable alumina as a binder, are to be presented. Volume stable mixes, after firing at 1600 deg C. with permanent linear change less than 1 percent, have been obtained. Means for compensating for the volume expansion due to in-situ spinel formation are revealed. Influences of the types and amounts of aluminas as well as synthetic spinel fine grains, in the matrix (alumina-or magnesia-rich spinel) are detailed Conclusion on the optimal mixes to produce better basic castables are drawn.