Microstructure andphase stability of Y–PSZ codoped with MgO or CaO prepared via polymeric route

Abstract

Fully dense nanostructured Y-PSZ ceramics with microstructural uniformity and stable high temperature zirconia phases were prepared by hot pressing at 1400°C. The addition of 1 mol-% MgO or CaO as codopant has a significant influence on grain growth characteristics. Addition of MgO tends to promote densification during sintering and assists in the preparation of nanosized material (<200 nm grain size) with uniform microstructure. X-ray diffraction investigations of samples hot pressed at 35 MPa and 1400°C for 20 min and thermally etched at 1350°C for 3 h showed the presence of three zirconia phases, cubic, tetragonal, and monoclinic. The existence of the cubic phase with the two other phases is associated with a fine crystallite structure. T his desirable microstructure, combined with good stabilisation of the high temperature phases, was recorded in nanostructured samples codoped with 1 mol-% of either MgO or CaO.