Alumina Composites with Metal Particles in Ceramic Matrix

Ceramic-metal composites are an important group of materials for many applications due to their unique properties. The combination of the hardness, strength at high temperatures, chemical inertness of ceramics with ductile, electrical or magnetic properties of metal are not achieved in single-phase materials. However, the brittleness of ceramics is the main disadvantage, which is limiting the under stress performance of ceramics and ceramic matrix composites. Theoretical and experimental research is still concentrated on improving the fracture toughness by tailoring the microstructure of composites. The study of metal particles embedded into ceramic particles, their distribution, size, and the interfaces and their influence on mechanical properties of the composites are presented. The important role of production techniques is emphasized. Based on experimental results, the Al2O3-Ni system is discussed.