Synthesis and Study of the Properties of Corundum-Mullite Ceramic as a Component of Ceramic Composite Materials

Abstract

The conditions for the synthesis of mullite-corundum ceramic prepared on the basis of Al₂O₃ and SiO₂ powders were investigated. The composition of mullite-corundum ceramic with Al₂O₃ < 80 wt.%, which affords the best thermomechanical compatibility with molybdenum, was determined. The possibility of obtaining a composite material based on a mullite-corundum matrix and molybdenum, as well as its use as a barrier layer at the Mo–Si-containing ceramic interface, was confirmed. It was ascertained that the use of a barrier layer substantially reduces the likelihood of thermal stresses arising at the interface between two phases. It is demonstrated that the technological parameters of the process of preparing Al₂O₃–SiO₂ powder mixtures require elaboration in order to increase the thermochemical compatibility of molybdenum with mullite-corundum ceramic.