Mechanical properties of zirconia toughened alumina with 10–24 vol.% 1Y-TZP reinforcement

Zirconia toughened alumina ceramics have found broad applications in industrial scale as they can provide high strength, toughness and wear resistance. Processing and compositional parameters have to be properly adjusted to achieve optimum mechanical properties. ZTA ceramics with an yttria content of 1 mol% and zirconia contents ranging from 10 to 24 vol.% were hot-pressed at 1475 °C at 50 MPa axial pressure and different dwell of 1–3 h. Stabilization of the reinforcement phase in ZTA with yttria was performed by a nitrate coating process of monoclinic zirconia nanopowders and subsequent blending with sub-micron size alumina. Microstructure and mechanical properties were investigated. A high ISB toughness of 8.5 MPa √m in combination with a 3-point bending strength of 1198 MPa was determined for the 1 mol% yttria 17 vol.% ZTA overmatching previous studies of coated ZTA ceramics. The interaction between stabilizer and reinforcement phase has a strong influence on the mechanical properties.