Fabrication of Infrared-Transparent Y₂O₃-MgO Nanocomposite Ceramic and Its Properties

Y2O3-MgO nanocomposite powders with different Y2O3/MgO ratios were prepared by ball milling using commercial Y2O3, MgO powders as the starting materials. The crystal structure, morphology, and composition as well as its uniformity of the Y2O3-MgO nanocomposite powder were characterized by XRD, SEM, and EDS, respectively. And then the hot-pressing was used to prepare infrared-transparent Y2O3-MgO nanocomposite ceramic. The FTIR and Vickers hardness tester were used to reveal the optical and mechanical properties of the Y2O3-MgO nanocomposite ceramic with different preparation parameters. The effects of critical parameters such as powder ratio, hot-pressing temperature, holding time of temperature and pressure on the particle size, densification, and the optical and mechanical properties of the nanocomposite ceramic were also researched. Results show that the transmittance and hardness reach to 80% (6 mu m) and 12.3 GPa, respectively, with optimal conditions (sintering at 1500 degrees C/15 min with Y2O3:MgO=1:1).