Stability properties and microstructure properties of microwave-sintered CeO2 doped zirconia ceramics

Nanosized CeO₂–ZrO₂ powders prepared by atmospheric pressure pyrolysis were used as raw materials to prepare CeO₂–ZrO₂ ceramics using microwave sintering. The samples were characterised using bulk density measurements, X-ray diffraction (XRD), Fourier Transform Infrared Spectrometer (FT-IR), Raman, and scanning electron microscopy (SEM). The purpose was to determine the optimised microwave sintering process for CeO₂–ZrO₂ ceramics and reveal the corresponding mechanism. The results show that with a CeO₂ addition content above 5 mol%, the tetragonal phase peak appeared obviously in the sample. The results show that the tetragonal phase peak appears when the CeO₂ content is more than 5 mol%. The dopants, namely CeO₂, have reduced the solid solution's phase transformation temperature with the assistance of microwave heating. Additionally, the grain size of the CeO₂–ZrO₂ ceramics has shown a negative relationship with Ce content at a temperature of 900 °C. The reason is that the rapid sintering due to microwave sintering and the oxygen vacancies generated by CeO₂ can effectively inhibit grain growth. The regulation mechanism on microwave sintering of CeO₂–ZrO₂ ceramic was clarified, and the technical prototype of controlled prepared CeO₂–ZrO₂ ceramics by microwave sintering was constructed.