Al2O3-Based Ceramic Composites with a High Brittle Fracture Resistance

Abstract

We examine synthesis conditions of precursors to ZrO₂–Al₂O₃–CeO₂ powders modified with calcium cations. The precipitation procedure and the aging of reaction systems of precursors to the synthesized composites are shown to influence the morphology and particle size of the nanopowders and the evolution of the phase composition, microstructure, and mechanical characteristics of composites prepared from them. The composites offer a high brittle fracture resistance due to the combined effect of transformation and dispersion hardening owing to the presence of T-ZrO₂-based solid solutions and calcium hexaaluminates (bending strength, up to 1000 MPa; fracture toughness K_Ic, up to 10.5 MPa m^1/2).