Advanced Ceramics for High-Temperature Radar Windows

The Challenge

Radomes must protect radar systems while remaining transparent to electromagnetic radiation. For high-speed aerospace applications, these components must maintain both structural integrity and RF transparency at extreme temperatures. Developing ceramic materials that achieve this balance requires precise control of porosity and microstructure through advanced manufacturing methods like slip casting and pressureless liquid phase sintering.

The Solution

This dissertation research explored porous silicon nitride as a radome material, using slip casting combined with pressureless liquid phase sintering as manufacturing methods. The GrindoSonic MK7 enabled measurement of elastic modulus in porous silicon nitride samples, providing data to correlate porosity levels with both mechanical strength and dielectric properties. This non-destructive characterization approach supported process optimization for achieving target property combinations required for RF window applications.

Key takeaway: Non-destructive elastic modulus measurement enables rapid screening of porous silicon nitride samples, linking porosity to both mechanical and dielectric performance without destroying candidate radome materials.

Results

The research advances material solutions for next-generation defense and aerospace systems by establishing processing-property relationships for porous silicon nitride radomes. Understanding how porosity affects both mechanical performance and electromagnetic transparency enables design of components that can withstand high-temperature operational environments while maintaining required RF window functionality.