Investigating Flexural Failure in Carbon Fiber Reinforced Polymer Composites Interleaved with Carbon Nanotube Sheets

摘要

While carbon fiber reinforced polymer (CFRP) composites exhibit exceptionalmechanical properties in tension, their relatively low compressive strength is often alimiting design factor. To mitigate this shortcoming, this study investigates effects ofinserting aligned carbon nanotube (CNT) sheets at ply interfaces on flexural propertiesof CFRP composites. CNT sheets were placed between carbon fiber plain-weavefabrics prior to infusion with epoxy. Resin transfer molding (RTM) was subsequentlyused to fabricate the specimens. Composite specimens were examined after fabricationand similar quality for both CNT interleaved and reference samples were observed.Samples were tested for on-axis tensile and flexural properties where the aligned CNTsheets were parallel to the bending direction. As expected, on-axis tensile tests showedno change in stiffness due to CNT reinforcement. The addition of CNT sheetsincreased the flexural strength by 28.9% and improved the resistance to delaminationcompared with the reference samples. This study suggests an innovative, inexpensiveand scalable solution for mitigating the low compressive and interlaminar properties ofconventional composites while potentially improving their physical properties such aselectromagnetic interference (EMI) shielding and electrical/thermal conductivities.Keywords: Carbon Fiber Polymer Composite, Carbon Nanotube Sheets, CompressiveStrength, Flexural strength.