Effect of sintering atmosphere on optical, mechanical, and thermal radiation performance of Y2O3–MgO composite ceramics

Y₂O₃–MgO composite nanopowders were prepared by sol–gel method, and Y₂O₃–MgO composite ceramics were prepared in oxygen (Y-M-O₂), air (Y-M-A), and vacuum (Y-M-V). The influence of the sintering atmosphere on the microstructure and properties of the Y₂O₃–MgO nanocomposite ceramics was examined. The findings indicate that sintering in a vacuum atmosphere enhances the concentration of oxygen vacancies in the ceramics, resulting in a marginal increase in their average grain size and consequently, an increase in density. Concurrently, the expulsion of internal pores leads to improved transmittance and hardness, while suppressing emissivity. Consequently, the microstructure, mechanical, optical, and thermal radiation performance of Y₂O₃–MgO nanocomposite ceramics are correlated with the concentration of oxygen vacancies, which can be manipulated by adjusting the sintering atmosphere. This research offers a viable strategy for enhancing the performance of Y₂O₃–MgO nanocomposite ceramics through simple control over the sintering atmosphere.