Interaction Between ZrB₂–MoSi₂ Cermets and Oxide Melts

Abstract

The contact interaction of ZrB₂–MoSi₂ materials with oxide melts is studied. The oxide melts are formed during combustion of low-reaction coals containing 30–49 % oxides. It is established that ZrB₂–MoSi₂ composites are wetted with oxide melts (the contact angles being 21–5 ° depending on material composition) at 1600–1700 °С in wetting conditions as well as during interaction for 6 h. A thin layer (~5–15 µm) forms in the contact zone, SiO₂ and ZrО₂ being its main phases. There is a great number of MoО₃, СаО, and Fe₂O₃ oxides at the boundary of these phases. The contact layer serves as film protecting the composite material against further corrosion in oxide melts. The optimum composition of ZrB₂–MoSi₂ ceramics, which can be used as corrosion resistant in oxide melts, is determined.