Application of Tomographic Imaging to Structural Ceramics: Green-State Monolithics and Ceramic-Ceramic Composites*

Monolithic ceramic materials such as SiC, Si3N4, Al2O3, and ceramic-ceramic composite materials such as SiC-reinforced Al2O3, SiC-SiC, and SiC-reinforced glass are emerging as important engineering structural materials. A major problem with using ceramic materials in engineering structures is the lack of reliability. The low reliability is caused by unreliable mechanical properties which are usually caused by internal flaws such as cracks and pore clusters in monolithic materials and clustering of whiskers and whisker stratification in composite materials. Design methodology with brittle solids is in its infancy and nondestructive examination methods which can be used to detect the load limiting flaws are necessary before the ceramic materials can be reliably used.