Development of Low Cost Needled C/SiC for TDACS Applications

This Phase II proposal is submitted under topic MD05-066 and continues the develop-ment of low cost, needled C/SiC for throttleable divert and altitude control systems (TDACS). The TDACS is being developed to guide the kinetic weapon of the Navy’s Standard Missile-3 to the target. The throttleable solid rocket motor technology embodied in the TDACS increases the range, standoff distance, and engagement area of SM-3. A TDACS motor, which has been successfully ground tested by Aerojet, employed nee-dled C/SiC composites from General Electric Ceramic Composite Products (GE) for some of the hot structural components. While the GE components performed well, the material is time con-suming and expensive to produce for two reasons. First the needled carbon fiber preforms are purchased from France, and second the chemical vapor infiltration process requires a lengthy high temperature furnace cycle. Furthermore, because the French-supplied needled preform is not optimized for the TDACS application, the performance and reliability of the needled C/SiC components can be improved if the material is designed based upon the requirements of the TDACS motor. This Phase II proposal seeks to build on the Phase I results that identified improved de-signs for needled C/SiC TDACS components, and pointed toward improved preox fabric con-figurations for needled preforms. The Phase II program will 1) fabricate and characterize a vari-ety of composite configurations to provide an alternate, inexpensive domestic source for needled C/SiC, and 2) design the composites so they exhibit properties that optimize performance of sev-eral TDACS hot gas components. The component designs will be developed by Materials Re-search & Design (MR&D) using a combination of micromechanical and thermostructural models to audition needled C/SiC composites. The composites will employ needled carbon fiber pre-forms manufactured by Textile Engineering and Manufacturing (TEAM) in Slatersville, RI. The composites will be densified by Goodrich-Supertemp in Santa Fe Springs, CA leveraging their CMC production furnaces. Additional material will be densified at GE to provide baseline data and investigate less expensive densification via polymer impregnation and pyrolysis (PIP). Southern Research Institute (SoRI) will measure the critical properties. The measured data cou-pled with the design results will lead to the selection of specific materials and component designs for ground testing as TDACS components. The proposed approach simultaneously defines the composite material and structural configuration leading to a more cost effective development program than existing “cut and try” methods.