Analysis and Modeling of Foreign Object Damage (FOD) in Ceramic Matrix Composites (CMCs) Navy STTR FY2010.A Sol No.: Navy STTR FY2010.A Topic No.: N10A-T010 Topic Title: Analysis and Modeling of Foreign Object Damage (FOD) in Ceramic Matrix Composites (CMCs) Proposal No.: N10A-010-0626 Firm: ALPHA STAR 5199 E. PACIFIC COAST HWY SUITE # 410 LONG BEACH, California 90804-3382 Contact: FRANK ABDI Phone: (562) 985-1100 Web Site: http://www.alphastarcorp.com Abstract: A significant barrier to the insertion of ceramic matrix composite (CMC) materials into advanced aircraft engines is their inherent lack of toughness under foreign object Damage (FOD) as well as post FOD. Our team will develop and demonstrate a physics-based model for FOD/post FOD in CMC's. The model will incorporate physical mechanisms associated with impact for two different CMC systems: a) matrix-dominated system and b) fiber-dominated system. Our methodology will address impact and post-impact of both "as-built" and "as-is" CMC's. It will account for architecture (2D/3D-nano) and CMC manufacturing (layered thickness, void shape/size, interfacial strength, micro-crack formation) taking advantage of the strength and toughness enhancing effect of different length scales of CMC structure. The model will be incorporated into our commercial progressive failure analysis software GENOA, that integrates commercial FEA and enhances their accuracy limitation. It will be validated using available CMC impact test data from NAVAIR SiC/SiC and Oxide/Oxide for a range of FOD tests. We will determine the feasibility for performing impact tests with Acoustic Emission/Electrical Resistance monitoring as damage assessment and health monitoring techniques that relates to damage model and life prediction. In Phase II high temperature impact testing will be conducted to further validate our model. Benefits: The application of CMC engine parts in advanced aircraft allows engines to operate at higher temperatures and significantly reduces engine weights. The analytical modeling strategy in CMC gas turbine engine development, as proposed herein, is a significant advantage in terms of reducing concept-to-commercialization time. This approach will result in the development of a verifiable analytical/design tool for optimization of CMC architecture and manufacturing processes. A novel approach to significantly enhance impact toughness of both SiC fiber-based, as well as Oxide fiber-based CMC's will bring these technologies closer to reality and enable the transition of these advanced material technologies to various military aircraft propulsion systems. Future use of these technologies can include hypersonic, space Thermal Protection System, and DOD aircraft parts as well as various DOE/NASA sponsored industrial power generation and aerospace related engine development programs. It has been demonstrated through a number of prior studies that ceramic matrix composite based material technologies will offer large economic and social benefits. With successful broad-based implementation, it can result in billions of dollars of cost savings and billions of tons of pollution reduction over the next couple of decades. FOD resistant CMC will allow life/durability to increase, enhancing time-on-wing and increased affordability. Return