Phase and microstructure evolution of Sc2O3–CeO2 –ZrO2ceramics in Na2SO4 + V2O5 molten salts.

In this study, the destabilization resistance of Sc 2 O 3 and CeO 2 co-stabilized ZrO 2 (SCZ) ceramics was tested in Na 2 SO 4 + V 2 O 5 molten salts at 750°C–1100 °C. The phase structure and microstructure evolution of the samples during the hot corrosion testing were analyzed with X-ray diffraction (XRD), Raman spectra, scanning electron microscopy (SEM), energy dispersive X-ray spectrum (EDS), and X-ray photoelectron spectroscopy (XPS). Results showed that the destabilization of SCZ ceramics at 750 °C was the result of the chemical reaction with V 2 O 5 to produce m-ZrO 2 and CeVO 4 , and little ScVO 4 was detected in the Sc 2 O 3 -rich SCZ ceramics. The primary corrosion products at 900 °C and 1100 °C were CeO 2 and m-ZrO 2 due to the mineralization effect. The Sc 2 O 3 -rich SCZ ceramics exhibited excellent degradation resistance and phase stability owing to the enhanced bond strength and the decreased size misfit between Zr4+ and Sc3+. The destabilization mechanism of SCZ ceramic under hot corrosion was also discussed. [ABSTRACT FROM AUTHOR]