Evaluation of silicon nitride reinforced silica aerogel composites for radom application

Abstract

Thanks to its lightness and superior mechanical properties, advanced technology
composite materials have a wide range of use in aviation, not only in interiors, but also
in the production of structural parts. The radom in the nose of the aircraft is one of the
areas of use of advanced technology composite materials. Silica aerogels with high
specific surface area (500–1200m2/g), low density (approx. 0.003–0.5 g/cm3), low
thermal conductivity (0.005–0.1 Wm-1K-1), ultra-low dielectric constant (1.0–2.0) and
low dielectric loss (10-2 – 10–4) are potential materials for use in radom application.
Recently, with the rapid development of aviation technologies, the speed of aircraft has
improved significantly. This situation revealed the necessity of increasing the high
temperature performance of silica aerogel radomes. Silicon nitride is a promising
structural-functional reinforcement phase for silica aerogel radomes due to its excellent
thermo-mechanical and dielectric properties. In this study, studies and results of silica
aerogel composites reinforced with Si3N4 are presented and discussed.