Enhanced thermal shock resistance of zirconia ceramics with multi-component rare earth and tourmaline addition

Abstract

To broaden the application of zirconia ceramics in high-temperature environments, continuous attempts to improve their thermal shock resistance remain the focal point. In this work, 1–4 wt% tourmaline-doped 10 mol% CeO2-3 mol% Y2O3-1 mol% Yb2O3 costabilized zirconia ceramic(10Ce3Y1Yb) was prepared. The phase composition, microstructure, and thermal shock resistance of composite ceramics were investigated by XRD, Raman spectroscopy, SEM, TEM and water-quenching experiments. The results indicate that composite ceramics exhibit excellent thermal stability of the tetragonal phase, which is attributed to rare earth stabilizer doping. Mullite whiskers formed by tourmaline transformation could enhance the resistance of crack propagation and reduce the coefficient of thermal expansion of composite ceramics, thus improving the thermal shock resistance of composite ceramics. Both the results of the water-quenched experiments and calculations of the thermal stress crack stability parameter (Rst) indicated an improved thermal shock resistance of tourmaline-doped 10Ce3Y1Yb ceramics, with an increase in the residual strength retention ratio from 20.36% for 3 mol% Y2O3-stabilized zirconia (3YSZ) to 41.56% for 3 wt% tourmaline-doped 10Ce3Y1Yb ceramics.