Thermal Stability and Ionic Conductivity of Calcia‐Stabilized Zirconia with Alumina Addition

Abstract

The thermal expansion and ionic conduction of 15 mol% CaO‐stabilized zirconia (CSZ) with added Al2O3 were investigated. Specimens with 0.5 and 1 mol% Al2O3 maintained the cubic phase, and the thermal diffusivity increased from 0.499 to 0.661 mm2/s with a 1 mol% addition. The addition of 5 mol% caused a decrease in the thermal diffusivity (0.609 mm2/s) with the formation of the monoclinic phase. The thermal expansion coefficient of the CSZ decreased, and the thermal diffusivity increased with the addition of Al2O3. The ionic conductivity was increased up to the addition of 1 mol% due to scavenging of siliceous by Al2O3, while the 5 mol% addition showed a decrease in conductivity with the formation of the intergranular phase.

Corrosion Resistance of Partially Stabilized Zirconia Materials to Alkaline Steel Slag

“…This indicates that the radii of Ca 2+ , Mg 2+ , and Y 3+ are similar to that of Zr 4+ , and that their solubility in ZrO2 is very high [11]. In the process of high-temperature sintering, Ca 2+ , Mg 2+ , and Y 3+ ions replace Zr 4+ ions to form a solid solution with ZrO2 [12]. This solid solution changes the internal structure of the ZrO2 crystal, inhibiting its transformation of ZrO2, meaning that the cubic phase is preserved at room temperature and that the samples are therefore composed of cubic (c-ZrO2) and monoclinic zirconia (m-ZrO2) phases [13].…”