Dispersion Hardening of Composites in the System Aluminum Oxide and Cerium Cation Stabilized Tetragonal Zirconium Dioxide

Resumo

The production of composites based on nanopowders synthesized by the sol-gel method in the system aluminum oxide and tetragonal zirconium dioxide stabilized by cerium cations (Al₂O₃–[Ce–TZP]) is described. It is shown that modification of the compositions by calcium oxide promotes the formation of composites of a dispersion-hardening phase in the form of long-prismatic grains in the sintering process. The presence of this phase affects the increase of strength and resistance to brittle fracture of composites with a ZrO₂ matrix and with an Al₂O₃ matrix. The strength in static bending of the composites reaches 1000 MPa and the cracking resistance K_1c increases to 11.0 MPa·m^1/2.