RESILIENT BEHAVIOR OF ADDITIVE MANUFACTURED CF/NYLON ORIGAMI HYBRID COMPOSITES FOR AEROSPACE DAMPING

The main aim of this investigation is to evaluate and compare the energy dissipation characteristics of origami-inspired structures (OIS) constructed from two different materials: discontinuous carbon fiber-reinforced Nylon (CFRN), commercially known as Onyx, and neat Nylon. Circular (COS) and square cross-section (SOS) OIS will be analyzed and hybridized with a plate lattice, resulting in circular origami (COPH) and square origami plate hybrids (SOPH), maintaining a consistent relative density of 20% across all structures. The initial step involves subjecting the structures to quasi-static compression at a strain rate of 2.5 mm/min to determine their maximum effective force within the linear elastic limit. Subsequently, these pre-determined loads will be applied as the OIS undergo cyclic loading at various strain rates (0.25,2.5, 25 mm/min) for up to five cycles within the linear elastic limit. This aims to observe the viscoelastic phenomenon and energy dissipation (ED) behavior. The study will analyze the effect of strain rate on the cyclic response and ED of monolithic and CFRN OIS by recording load-displacement hysteresis loops. Wider loops indicate more viscoelastic behavior and greater energy dissipation, suggesting suitability for damping applications. The investigation will particularly explore the impact of discontinuous carbon fibers on the viscoelastic behavior and energy dissipation of both curved crease OIS and their plate hybrid counterparts. The neat Nylon OIS may exhibit higher energy dissipation (ED) but also demonstrate greater viscoelasticity, which is not ideal for prolonged or repeated cycles. Conversely, the composite origami-inspired structures (OIS), despite displaying lower ED and less viscoelastic behavior, are thought to consistently dissipate energy over an extended number of cycles. The incorporation of CFRN enables the design of OIS with adjustable stiffness and dissipation characteristics.