An experimental investigation into flexural properties of hybrid carbon-basalt triaxially braided composite lamina

Here, an investigation was conducted to evaluate the effect of intralayer hybridization with basalt fibers on the flexural moduli of triaxially braided carbon/epoxy composite lamina (3AXB). Four 3AXB preforms were produced using a circular braiding machine and were fabricated into a composite lamina via vacuum bag assisted resin transfer technique using epoxy resin. Then, three-point bending tests were performed on the prepared four specimens according to ASTM D790 with a large span-to-depth ratio in both longitudinal and transverse directions to determine their flexural moduli. Test results showed that hybrid 3AXB composites with carbon fibers as axial yarns and basalt fibers as braid yarns showed similar flexural performance in longitudinal direction in comparison to all-carbon 3AXB composite. Similarly, hybrid 3AXB composites with basalt fibers as axial yarns and carbon fibers as braid yarns showed similar flexural performance in transverse direction in comparison to all-carbon 3AXB composite. These indicate that, under specific circumstances, there is a possibility to reduce the overall cost of all-carbon 3AXB composite without compromising its flexural performance. Besides, a multi-scale finite element model was performed to predict the flexural stiffness of 3AXB composites.