Bearing/bypass interaction of a three-dimensional woven carbon composite
The objective of this paper is to investigate the bearing/bypass interaction of a carbon fiber reinforced three-dimensional woven ply to ply composite. The composite was reinforced with a three-dimensional woven ply to ply preform and injected with PR520 epoxy resin using a resin transfer molding (RTM) process. The preform was woven with 24K IM7 carbon fiber tows in the warp and weft directions. Results of filled-hole tension and compression, single-fastener bearing, and double-fastener bearing are presented and discussed. All bearing experiments are single-shear and include supported single-fastener tensile and compressive loading, and supported double-fastener tensile and compressive loading. A 6.35 mm nominal diameter Hi-Lok steel alloy pin with an aluminum alloy collar was used for filled-hole tension and compression, as well as for all bearing experiments. The experimental study presented in this paper demonstrates that a practical bearing/bypass interaction diagram can be constructed for a three-dimensional woven composite using the same procedures and standardized test methods recommended in the literature for two-dimensional laminated composites. Representative stress-strain curves for filled-hole tension and compression are presented, as well as for single-fastener bearing and double-fastener bearing under tensile and compressive loading. Findings and practical recommendations on the bearing/bypass performance of the three-dimensional woven composite are also discussed.