Creep of Non—Oxide Ceramics Considering Oxidative Influences
Creep of silicon nitrides and silicon carbides is considered, including the effects of oxidation. Basic behaviour is defined, the relevant background equations presented, and the parallel microstructural mechanisms discussed. For porous silicon nitride the pore size rather than amount is critical in determining creep under oxidation. In dense sintered silicon nitride the presence or absence of viscous glassy phases is the main factor controlling behaviour. Silicon carbide ceramics show relatively low creep rates and are not so sensitive to oxidation effects.