Abstract:
Much of the development of fiber-reinforced composites for additive manufacturing has been efforts to meet or exceed the performance of traditionally processed metal alloys. Additive Manufacturing (AM) with carbon fiber reinforced filaments has the potential to leverage the anisotropic nature of composites to increase the strength of components where needed without adding weight or bulk. One potential area to leverage this native anisotropy is around fastener holes. As bolted joints typically constitute the weakest part of a composite component, in this investigation we aim to determine if they may be strengthened by controlling the orientation of fibers around the hole. To this end, we compare bolt bearing testing results using NylonX material printed with two different bolted joint types: manufactured-in-place, or “printed-in”, allowing for fiber orientation circumferentially around the hole, and post-drilled, and find dramatic difference in observed mechanical properties between the two hole generation methods.