High Temp Standoff Dielectric Antenna Windows Based on 3-D Woven Preforms

The speed of supersonic cruise missiles generates surface temperatures that can exceed the limitations of even high temperature structural metals like titanium. Insulation to protect electronics equipment in the missile is typically a parasitic thermal protection system. A multi-functional solution that has the potential of revolutionizing the design and performance of missiles, re-entry vehicles, and other hot flight structures is an oxide-oxide CMC based on a 3-D woven preform that integrates the thermal protection system. Structures based on oxide-oxide systems can withstand the anticipated temperatures of ~1200-1500oF at lower cost than SiC-SiC. The 3-D fiber architecture will increase the fracture toughness and interlaminar strength of the CMC, while multi-rapier 3-D weaving enables the economical production of 3-D woven preforms and the integration of the thermal protection system. Further, the oxide-oxide systems of interest exhibit dielectric properties that make them of particular interest for antenna windows integrated into the vehicle skin. Therefore, the primary objective of the proposed program will be to develop capabilities to design, fabricate, and evaluate a new class of hot-structure panels that combine thermal protection and structural elements in a single integrally formed component for use as acreage surfaces and as antennae windows for supersonic missiles.