Fabrication of infrared-transparent Y2O3–MgO composites using nanopowders synthesized via thermal decomposition

Abstract In this study, pure and fine composite nanopowders with equal volume fractions of Y2O3 and MgO were synthesized via thermal decomposition of nitrate mixtures at a relatively low temperature (600°C). To improve the performance of the synthesized nanopowders, thermal decomposition under different heating rates were performed and the influence of milling conditions were investigated. Fully dense Y2O3–MgO composites were prepared by pre-sintering the Y2O3–MgO nanopowders in air, followed by hot isostatic pressing. The prepared Y2O3–MgO composites did not contain carboxylate groups and exhibited excellent infrared transmittance over the 3–7.5 μm range.