LAUSR

Abstract Y2O3-MgO nanocomposite powder was synthesized by a microwave technique and doped into gas-pressure sintered BN/Si3N4 composites to acquire a highly wave-transparent material that could be utilized in spacecrafts. The XRD and SEM analyses indicated that the main phases were rod-like β-Si3N4 particles and MgSiO3. In this case, a BN/Si3N4 ceramic with 8 wt% Y2O3-MgO nanopowder displayed a density of 2.5 g/cm3. The permittivity and transmission efficiency were approximately 4.6% and 71.4%, respectively, at frequencies of 8.2–12.4 GHz, which achieved the best overall wave-transparent performance. The porosity of the material in combination with the inclusion of the boron nitride component creates a synergistic effect that appears to contribute to wave-transparent efficiency.