Polycrystalline Alumina for Aerodynamic IR Domes and Windows

摘要

CeraNova's transparent polycrystalline alumina (CeraLumina?) has sub-micron grain size (300-500nm) and high transmittance in the mid-wave infrared (>85% in the 3-5μm MWIR region). The fine, uniform grain size imparts high hardness, high strength, and high thermal shock resistance. Polycrystalline alumina is a viable alternative to sapphire for domes, particularly for aerodynamic shapes which are readily fabricated by powder processing. Both hemispheric and ogive domes (sub-scale and full-size) have been successfully molded and densified to transparency. Hemispheric domes have been optically finished. Current efforts include a focus on scale-up, fabrication, and metrology of aerodynamic domes. This paper presents recent analyses of microstructure, optical properties, and mechanical properties.