Manufacturing and Properties of Ceramics Originated from Zirconia-Ceria Nanopowders Doped with Yttria

摘要

Ceria-zirconia nanopowders doped with yttrium(III) oxide were prepared by a soft chemistry route. A concentration of ceria in the 8 mol% yttria-zirconia nanopowder changed from 0 to 100 %. In the route, a water solution of zirconium(IV) oxychloride, yttrium(III) chloride and cerium(III) nitrate was treated with ammonia to co-precipitate a deposit, which was calcined for 2 h at 900°C in air to obtain crystalline nanopowder. Consolidation of the nanopowders was performed by means of cold isostatic pressing under 220 MPa and natural sintering for 2 h at 1550°C in air. The effects of the ceria concentration on properties of both yttria-zirconia-ceria nanopowders and bulk materials were investigated by TG-DTA, XRD, BET, SEM and Vickers' indentation. The thermal behaviour of co-precipitated materials, crystal structure and crystallite size of the nanopowders, evolution of the microstructure and mechanical properties of the bulk materials were found to depend on ceria concentration.