Structurally Efficient Composite Concepts for Future Military Air Vehicles

The objective of the proposed research is to develop both an advanced design methodology and an innovative process for designing and manufacturing novel composite materials for future military air vehicles. The proposed new design methodology, referred toas function-oriented material design (FOMD), will provide an effective tool for the optimal design of structurally efficient composites, such as those with optimally-shaped cellularity or, in fiber-reinforced composites, optimal arrangement of the fibers(made of carbon or other materials including metals). The proposed new manufacturing methodology, referred to as the biomimetic process, will be developed to fabricate, in a unique way, the optimal design obtained from the FOMD process, thus resulting ina new generation of highly efficient and versatile structural materials. With the design tool developed in this program, new materials will be optimally designed in order to meet the requirements for advanced structural performance and weight reduction.For example, the materials in the main and secondary structures of an air vehicle will be designed with respect to their specific performance requirements, hence achieving optimal design in terms of both global and local performance. This will ensure thatthe weight of an air vehicle is distributed in the best possible way and that the structures are truly-optimally designed without waste of material. The proposed biomimetic fabrication process will provide substantial control at microscopic andmacroscopic structural levels, and cover broad ranges and combinations of materials and systems (ceramics, metals and polymers). This energy-efficient and cost-effective process can accommodate complex, three-dimensional geometric configurations, thuslowering the number of parts and joints. Gradient structures can also be conveniently introduced, which facilitates the development of efficient systems with structural materials concentrated along optimum load paths. The integrated nature of systems andthe high level of control over their gradient structure will provide designers with powerful tools for eliminating premature failure modes associated with local instabilities, out-of-plane bending, debonding, bearing and impact loads, and stressconcentrations.