Abstract: A transparent aluminum oxynitride product is produced by a first heat treating step wherein a combination of Al2O3 and AlN at a temperature within the solid-liquid phase and a second step of sintering the heat treated combination at a temperature at least 50° C. less than the heat treating temperature. The method introduces a small fraction of liquid that aids in pore elimination and densification. In a single step, the material is shifted from the liquid/solid region into a solid AlON solution region, wherein the liquid is fully reacted with the solid AlON phase, with further sintering occurring. The procedure is sufficient to eliminate voids and other imperfections which often result in a reduction in optical clarity.

Abstract: A ceramic nanocomposite made from silicon, oxygen and nitrogen is provided hich has a very low dielectric constant, low dielectric loss along with good strength and hardness. The ceramic nanocomposite finds use in millimeter-wave radomes and microwave radomes used on aircraft which must resist erosion from high speed impact with water, ice and dust in the atmosphere.

Abstract: A novel ceramic ferroelectric material having a low dielectric constant, loss and high tunability. The material is a composite comprising Barium Strontium Titanate (BSTO) and a ceramic material having a low dielectric constant. The preferred composite is represented by Ba.sub.1-x Sr.sub.x TiO.sub.3 -Al.sub.2 O.sub.3, wherein x is greater than 0.00, but less than or equal to 0.70, and wherein the percent weight ratio between Ba.sub.1-x Sr.sub.x TiO.sub.3 and Al.sub.2 O.sub.3 ranges from approximately 99%-40% and 1%-60%, respectively. The novel materials possess superior electronic properties; and they may be employed in various antenna systems.