Ballistic Missile System Composite Materials and Structures

igh performance interceptors have been pushing material designers to develop low cost radome solutions for the last several decades. Many solutions have been examined and engineered such as silica-silica, Pyroceram, IRBAS, GD-1, Rayceram, and SiN to name a few. Hit-to-kill mission designers have been increasingly pushing the envelope, much to material designers dismay. Despairingly, there has not been one material out of the entire family of ceramic radome solutions that has been a general solution for all mission criteria. Similarly, composite designers have not faired any better. Organic based composite laminates are suitable for low temperature (< 650°F) , low frequency (L,C, and S Band) applications but cannot survive the structural and electrical mission requirements at elevated temperatures. Inorganic laminates, similar to the MSI's quartz/polysiloxane solution can survive temperatures up through 1500°F for short durations (less than 180 seconds), however extending the footprint much beyond those parameters is suspect at this time. MSI's solution has not been subjected to parameters beyond these extremes. The intent of this proposal is to extend the footprint (illustrated in Figure 1.0) of MSI's composite radome solution using a reaction bonded silicon nitride as reinforcement in the laminate.