Physics-Based Non-Linear Behavior Models for Design of Carbon-Fiber Reinforced Composite Components

ABSTRACT: Innovative research and development leading to a dual-use advanced technology product is proposed. The product is a methodology and associated software for modeling nonlinear response of carbon-fiber reinforced composite materials such as carbon/carbon (C/C) and carbon/silicon-carbide (C/SiC), and design of their components. Once developed and validated, the methodology would be used in cost effective development of C/C and C/SiC components, such as Thermal Protection Systems (TPS) and missile cones by the Air-Force and its major hypersonic weapons suppliers. The proposed methodology would be applicable to a broad class of C/C and C/SiC components for military and commercial applications. An innovative Physics-Based mechanistic modeling approach is proposed. The approach, based on an existing validated modeling approach for SiC/SiC Ceramic-Matrix Composites, includes direct consideration of relevant defect and damage mechanisms and environmental degradation. Utilization of existing models developed for similar materials and building on them will result in shorter model development times and more efficient use of Air-Force resources. Phase I will include characterization of deformation and damage in mechanistic model for C/C and C/SiC materials mostly from literature in order to understand any deformation mechanisms unique to these material systems. The models will be validated against benchmark and sub-element test data. Predictions will be compared with experimental measurements to assess the modeling approach and feasibility for a comprehensive methodology development in Phase II. BENEFIT: Due to the proliferation in potential applications of C/C and C/SiC composites in military applications such as TPS and shields for hypersonic bodies, and in commercial applications, such as aircraft brakes, the proposed dual-use high technology product has an immediate and expanding market. The biggest benefit of the proposed product is in its ability to improve the design of carbon-reinforced composite components taking advantage of its inherent nonlinear behavior. SAI will market the methodology, the software and technical expertise (services) to these and other industries.