Damage self-sensing and strain monitoring of glass-reinforced epoxy composite impregnated with graphene nanoplatelet and multiwalled carbon nanotubes

The damage self-sensing and strain monitoring of glass-reinforced epoxy composites impregnated with graphene nanoplatelets (GNPs) and multiwalled carbon nanotubes (MWCNTs) were investigated. Hand lay-up and vacuum bagging methods were used to fabricate the composite. Mechanical stirrer, high shear mixer, and ultrasonic probe were used to mix the nanofiller and epoxy. The loadings of the nanofiller used were 0.5, 1.5, 3, and 5 wt%. The specimens were tested using in situ electromechanical measurements under mechanical tests. The results show that the type and weight content of the nanofiller affect the electrical properties, damage self-sensing behaviour, and mechanical properties of the composites. The electrical conductivity of the GNP-glass and MWCNT-glass composites increased with nanofiller content. The tensile and flexural strengths of the composite improved with the addition of GNP and MWCNT nanofillers from 0.5 to 3 wt%. The 3 wt% nanofiller loading for GNP and MWCNT produces better mechanical-electrical performance. Field emission scanning electron microscopy revealed the dispersion of GNP and MWCNT nanofillers in the composites.