Enhanced infrared transmission characteristics of microwave-sintered Y$_2$O$_3$–MgO nanocomposite

[摘要] Infrared (IR) transparent ceramics are found to have applications in demanding defence and space missions. Inthis work, Y$_2$O$_3$–MgO nanocomposites were synthesised by a modified single-step combustion technique. The characterisation of the as-prepared powder by X-ray diffraction and transmission electron microscopy revealed the presence of cubicphases of ultra-fine nanostructured Y$_2$O$_3$ and MgO, with an average crystallite size of $\sim$19 nm. For the first time the resistive and microwave heatings were effectively coupled for sintering the sample, and it was found that the sintering temperature and soaking time were reduced considerably. The pellets were sintered to 99.2% of the theoretical density at 1430$^{\circ}$C for a soaking duration of 20 min. The well-sintered pellets with an average grain size of $\sim$200 nm showed better transmittance properties relative to pure yttria. The promising percentage transmission of 80% in the UV–visible region and 82% in the mid-IR region shown by Y$_2$O$_3$–MgO nanocomposites can be tailored and made cost-effective to fabricate high-quality IR windows for strategic defence and space missions.

[学科分类] 材料工程

[关键词] Nanocomposites;infrared transparent window;hybrid sintering;transmittance;combustion synthesis.