Development of Fiber Reinforced Composite Feedstock for In-Space Manufacturing of High Strength Parts

The Phase I results have demonstrated the feasibility of using FDM, optimized feedstock combinations, and composite architecture to produce high strength parts. During Phase II, this initial success will be expanded on for this overall technology to become a feasible candidate for ISS accommodation. Accordingly, during Phase II the FDM unit will be modified to meet ISS compatibility standards and a prototype of this unit will be developed. In addition, the composite architecture, fiber layup, and feedstock combinations down selected from Phase I will be further optimized to improve structural capability beyond what was already achieved during the Phase I effort. Advanced feedstocks will be further developed not only for enhancement of structural properties but also from the perspective of outgassing. The team recognizes that for a true structural part built on the ISS, it may not be possible to conduct comprehensive mechanical testing on ISS to validate the part itself. During Phase II, a comprehensive finite element modeling (FEA) approach will be undertaken to predict mechanical properties as a function of feedstock combination and composite configuration. This FEA model will be validated using extensive mechanical and fracture testing data. Such a validated model will be a useful tool to select feedstocks and composite architecture combinations prior to printing a part on the ISS. Sufficient testing of down selected feedstock combinations and composites will be conducted to develop at least an S basis design allowable. We also propose to pursue FDM printing of metallic parts and demonstrate the potential of using the same FDM unit to print both composite and metallic parts. Development of such a versatile FDM unit will be a significant contribution to enhance ISS or NASArsquo;s FabLab capabilities by reducing the launch payload mass and reducing the footprint.nbsp;