Formation mechanism and characterization of gradient density in corundum–spinel refractory

Abstract

The existence of gradient density in lightweight corundum–spinel refractory is expected to reduce thermal conductivity, while ensuring good mechanical performance. In this study, the formation mechanism and characterization of density-gradient structure in refractory were revealed. The effects of the particular structure on physical, mechanical properties and thermal conductivity of the prepared lightweight refractory were also investigated. The results showed that the high density in external zone of the material could guarantee excellent physical properties and mechanical strength. Meanwhile, the high porosity in internal district was beneficial to reduce thermal conductivity and achieve energy saving. The unique structure and outstanding properties of the lightweight corundum–spinel refractory would endow it with a bright prospect in the application of industrial furnaces.