Infrared-Transparent Y2O3-MgO Nanocomposites Using Sol-Gel Combustion Synthesized Powder

Y2O3–MgO composite nanopowder with a volume ratio of 50:50 was synthesized using a sol–gel combustion process. X-ray diffraction analysis of the as-synthesized nanopowder shows phase pure Y2O3 and MgO with a cubic crystal structure and crystalline size ∼15 nm. The fully dense Y2O3–MgO nanocomposites were prepared by pressureless sintering the composite nanopowder at 1400°C for 2 h, followed by hot isostatic pressing at 1350°C for 1 h and postsinter annealing at 1000°C for 10 h. The Y2O3–MgO nanocomposite exhibit excellent infrared transmittance (62%–80%) over 3–7 μm infrared wavelength ranges with an average hardness of 10.6 GPa.