Laser Induced Graphene for <scp>EMI</scp> Shielding and Damage Detection in Kevlar/Basalt Hybrid Composite Laminates

ABSTRACT Basalt fiber (BF) reinforced polymer composites are widely used in military, construction, and marine engineering fields. However, the intrinsic electrical insulation of basalt fiber restricts its use in functional composite materials, particularly in applications such as electromagnetic interference (EMI) shielding. Laser‐induced graphene (LIG) is a form of three‐dimensional carbon nanomaterial, which could be generated by scribing a laser on carbonaceous precursors. This study utilizes laser‐induced graphene technology to generate graphene directly on the surface of Kevlar fabrics. The LIG‐modified Kevlar fabrics were then stacked with basalt fabrics to fabricate fiber‐reinforced epoxy hybrid laminates. The impact of LIG film insertion on the interlaminar fracture toughness of Kevlar/basalt hybrid laminates was evaluated using double cantilever beam tests. The electromagnetic shielding performance of the hybrid laminates with varying numbers of graphene layers was investigated. Raman spectroscopy confirmed the formation of multilayer graphene on the laser‐etched Kevlar fabrics. The EMI shielding effectiveness of the basalt fiber laminates increased to ~20 dB after three layers of LIG‐modified Kevlar were inserted, and to ~55 dB after seven layers of LIG‐modified Kevlar were inserted, for the X‐band frequency range. Damage localization within the hybrid laminates was achieved by patterning LIG films and monitoring changes in electrical resistance.