High-Performance Structural Ceramics: Powders and Components

Abstract

High-performance ceramics have attracted much interest during the last decade, but a broad market introduction has not taken place so far due to the inherent disadvantages of ceramic components in applications with high mechanical loadings. The high brittleness and the low reliability as compared to metals, as well as the high production costs are severe obstacles in an area like the automotive engine. Typical defects of ceramic components may be introduced by the powders themselves, but in a like manner, sources of defects also lie in the forming and the densification of the components. The production technologies used for high- performance ceramics are mostly the same that are applied in traditional ceramics. It is demonstrated exemplarily for the materials silicon carbide, zirconia, alumina and silicon nitride, exactly what the main sources of defects are and how they could be avoided. From this, the desired powder properties can be derived. It is expected that improvements in powder processing and forming technologies will improve the reliability of ceramic components and lower the costs, thus leading to the remarkable market growth which has been predicted for more than ten years.