Abstract
Coefficients of thermal expansion (CTEs) of ZrO2 particle/Al2O3 and ZrO2 particle /SiC whisker/Al2O3 composites were experimentally ditermined in the temperature range of room temperature to 1200K. In order to examine capability of CTE design of ceramic matrix composites, CTEs of constituent materials (monolithic ceramics) were also axamined. Temperature dependence and relative magnitude of CTEs for the monolithic ceramics were shown to be easily understood from the viewpoint of the relation of Grüeizen. Using the low of mixture based on the equivalent inclusion method, it was demonstrated that accurate design of CTE can be made, provided that temperature dependency and magnitude of CTE of SiC whisker is assumed to be smaller tcan that of the bulk SiC. This CTE behavior of SiC whisker was shown to be reasonable from the viewpoint of Grueisen relation and Ruffa's theory, because the theory leads to low CTE and slow and gradual increase of CTE with temperature when elastic modulus and thus the Debye temperature are becomes higher.
