Novel Ceramic Composites for Low Loss Hypersonic Radome Materials

As threats emerge in geographically diverse locations, precision responses are often required immediately.However, the time-to-target for many munitions can be simply too long for short lived opportunities.To enable timely responses to long range threats, hypersonic munitions with velocities greater than Mach 5 are necessary.However, with hypersonic velocities comes a significant increase in the aerodynamic heating and loading for missile components.In particular, the nosecone radome faces the challenge of very high aerodynamic heating in excess of 1093C (2000F) while requiring stable dielectric performance to maintain accurate guidance.Current radome materials are insufficient to provide the necessary thermo-mechanical stability at these elevated temperatures, while also providing good dielectric performance.In addition, characterizing the high temperature dielectric properties at the X-Ka band frequencies can be challenging for low dielectric constant materials.This work supplies three high strength material candidates for advanced hypersonic radomes:GdAlO3-Al2O3 composites, Yb-silicate composites, and B4C.A novel processing route is also proposed to simply fabrication for near net shape parts.Lastly, dielectric testing methods are identified for high temperature and high frequency testing in later stages of the project.