Fabrication and properties of Y2O3 transparent ceramic by sintering aid combinations

Transparent Y2O3 ceramics were fabricated by the solid-state reaction and vacuum sintering method using La2O3, ZrO2 and Al2O3 as sintering aids. The microstructure of the Y2O3 ceramics sintered from 1550 °C to 1800 °C for 8 h were analyzed by SEM. The sintering process of the Y2O3 transparent ceramics was optimized. The results showed that when the samples were sintered at 1800 °C for 8 h under vacuum, the average grain sizes of the ceramics were about 3.5 µm. Furthermore, the transmittance of Y2O3 ceramic sintered at 1800 °C for 8 h was 82.1% at the wavelength around the 1100 nm (1 mm thickness), which was close to its theoretical value. Moreover, the refractive index of the Y2O3 transparent ceramic in the temperature range from 30 °C to 400 °C were measured by the spectroscopic ellipsometry method.