Description: We propose an innovative hybrid composite material containing shear thickening fluid (STF) Energy Absorbing Layers (SEALs) that provides superior impact protection and novel, self-healing functionality to prevent leakage after impact. The proposed innovation directly addresses the need for thin, lightweight, impact-resistant composite materials that can be fabricated in complex geometries for next-generation space suits. The proposed Phase II research leverages successful Phase I R&D and extensive composite materials and space suit expertise of our partners to advance commercialization and TRL of impact-resistant, damage-tolerant SEAL-composites innovation to produce a prototype suit component suitable for system-level integration and testing. In Phase I it was shown that the SEAL-composites provide significantly improved impact properties and weight savings vs. leading conventional composite materials from the Z-2 prototype. Futhermore, SEAL-composites impart self-healing functionality to mitigate air leakage if damaged. The Phase II objectives and work plan follow a logical sequence to test and downselect improved SEAL-composite materials, to develop and validate a computational model and conduct model-based design optimization, to develop high-fidelity test methods, to refine the manufacturing process to make aerospace-grade SEAL-composites, and to deliver a validated suit prototype component made from SEAL-composites. Further, we will leverage synergistic environmental protection garment (EPG) research being conducted at STF Technologies and the University of Delaware to perform system-level development and optimization of the SEAL-composites combined with emerging, state-of-the-art EPGs. Overall, the proposed Phase II will produce a validated SEAL-composite prototype suit component meeting the needs for improved impact-resistance and damage-tolerance to offer superior astronaut protection in a wide range of future Martian and Lunar surface EVA scenarios.

Benefits: The primary target market for the proposed SEAL-composites innovation is in the composite portions of advanced xEMU and mEMU suits for future surface exploration missions. Specifically, the hybrid materials and design of the SEAL-composites provide significant increases in impact-resistance and damage-tolerance as compared to conventional composite materials. Phase I results found that the SEAL-composites tolerate 50% more impact energy without sustaining damage resulting in leakage and were 11% lighter than monolithic designs using the materials developed in the prior Z-2 prototype project. The improved durability and self-healing functionality at reduced weight of the SEAL-composites is useful for increasing the reliability of other composite structures and applications including storage tanks, habitats, or surface exploration vehicle components.

The growing market for carbon fiber and fiberglass composites represents a substantial market opportunity for STF composite materials offering improved impact resistance and damage tolerance. Improvement of out-of-plane impact resistance can potentially improve the durability and utility of composite materials in a wide variety of applications and industries including: 1. Automotive - an all composite B-pillar was recently demonstrated by researchers at UD CCM under a collaboration with BMW. Carbon fiber composites are also seeing increased demand in automotive due to the desire for increased fuel economy and growing demand for electric vehicles. 2. Personal Protective Equipment (PPE), including composite armor and shielding for first responders 3. Storage tanks for water, chemical process, oil and gas industries 4. Aerospace 5. Consumer sporting goods - skis, snowboards, surfboards, bicycle frames, tennis rackets, hockey and lacrosse sticks, helmets, and protective equipment 6. Power generation-increasing demand for wind turbine blades is major driver of growth in the fiberglass and carbon fiber reinforced composite market. Composite materials with damage tolerance and tunable damping properties have applications in large- and small-scale generation infrastructure. 7. Construction and building materials - building cladding, decking 8. Marine