Electric Field Assisted Through‐Thickness Alignment of Carboxyl Functionalized Graphene in Glass Fiber/Epoxy Laminates: Emphasizing Bending, Interlaminar Shear and Fracture Behavior

A possible way to enhance the Z‐directional mechanical characteristics of laminated GFRP composites is by suitable through‐thickness alignment of secondary reinforcements. In this work, efficient alignment of polar carboxyl functionalized graphene (FG) in a laminated GFRP composite has been achieved by optimizing the applied z‐directional A.C. field strength. The laminate AF300, where the field strength is 300 V/mm exhibited the best flexural strength among all the composites considered, which is 17% and 32% higher over randomly oriented FG embedded GFRP (RF) and neat GFRP composites respectively. Dynamic mechanical analysis also suggests similar effect where the storage modulus of AF300 composite was found to be significantly better over both RF and Neat composites. Short beam strength as obtained indicates efficient restriction towards delamination due to the through‐thickness alignment of FG. A substantial improvement in energy absorption during Mode I inter laminar fracture toughness (ILFT) test has been noticed due to alignment of FG in the GFRP composite. Similarly, AF300 composite exhibited 84% better Mode II ILFT over the neat composite. Through thickness electrical conductance of AF300 composite is 350% better than Neat and 80% better then RF composite, indicating successful alignment of FG along through thickness direction.