Unique Fabrication Process and Strategy for Complex Flight Structures

Hypersonic vehicles impose demanding thermal structural requirements on refractory C/C and CMC materials. The thermal and mechanical properties from small, standard test samples on which the design of specific hypersonic hot structure components are typically based are usually not duplicated in real flight structures. Manufacturing limitations in fabricating real structures versus thin, simple shape test specimens account for the compromised properties. This Phase 1 proposes to demonstrate the ability of a unique and rapid CVI process to produce equivalent, quality microstructures and properties in standard test samples and a thick complex shape that represents properties essential for flight structures. The effort includes testing of thermal conductivity and interlaminar tensile strength from samples taken from the simple and complex shapes at both room and elevated temperature that will be supplemented by microstructural analyses of as-fabricated and post test samples. A virtual model of this configuration will be used to embed a truss structure representative of the fiber tow architecture into a finite element mesh that simulates the matrix. The matrix elements will include cohesive elements to simulate potential delamination between separate regions (e.g., plies).