Hochfeste Keramiken auf Al2O3-Basis durch kontrollierte Korngrenzenstrukturen

Technological principles are discussed to develop pressureless sintered, single and polyphase non- nanocrystalline microstructures of isometric grain shape on the basis of Al2O3 with a strength of about 700 MPa avoiding dissipation mechanisms like transformation-, microcrack- or whisker-toughening and grain bridging. Two essentials are (i) the use of technologies which produce sintered parts with small flaw sizes and - to minimize subcritical crack growth - (ii) extremely perfect grain boundary structures.