Synergistic effects of multiwalled carbon nanotubes and graphene Nanofillers on the performance of hybrid Kevlar/carbon epoxy composites

The mechanical characteristics of hybrid composites are mainly influenced by reinforcing distinct types of fiber, nanofillers, matrix materials and fabrication routes. In this study, a coating of hybrid Multiwalled Carbon Nanotubes (MWCNT) + Graphene (GNP) on hybrid Kevlar/Carbon fibers is fabricated to enhance the interface/interphase between the fiber and matrix. Eight different types of composites are prepared with varying stacking sequences i.e. uncoated hybrid and coated with and without nanofiller weight fraction (i.e., 0 %, and 0.2 wt%). The MWCNT+GNP-hybrid fabrics were coated with a solvent spraying covering and built up into the laminates using vacuum vacuum-assisted resin transfer molding technique. The uncoated and MWCNT+GNP coated hybrid KCEC have been subjected to tensile, flexural, compression and fatigue tests, followed by detailed fractographic analysis. The tensile strength (8.96 %), compressive strength (22.74 %), flexural strength (31.18 %) and increased fatigue life by 52 % were observed with coating of 0.2 wt% MWCNT+GNP blended with hybrid KCEC composites compared with uncoated neat KCECs. The fractography analysis reveals a coating of MWCNT+GNP showing smaller debonding gaps along with larger adherence between fiber and epoxy analysis was performed through optical and FE-Scanning electron microscopy. These findings provide valuable insights for the design and development of high-performance, durable composite materials suitable for advanced structural applications.