Thermal expansion anisotropy in hot-pressed SiC-whisker-reinforced alumina composites

The measured linear thermal expansion coefficients α of hot-pressed SiC-whisker-reinforced aluminas decrease as the SiC whisker content is increased from 1 to 60 vol.%. However, owing to the preferred orientation of the whiskers, the α value for each SiC whisker content is greater in the direction parallel compared with the direction perpendicular, to the hot-pressing axis. The observed behavior is generally consistent with that predicted by a model based on the effects of internal thermal mechanical mismatch strains in composites with oriented reinforcements.