Enhancing structural performance of 3D‐printed adhesively bonded flat‐joggle‐flat polymer joints with graphene‐reinforced adhesive

Adhesively bonded joints play a vital role in improving the structural performance of 3D‐printed components. This research aims to examine the effect of graphene inclusion on the failure load and vibrational behavior of polylactic acid flat‐joggle‐flat (FJF) joints prepared using fused deposition modeling. The present research focused on the effect of print directions (0°, 45°, 90°) and the inclusion of graphene nanofiller (0.25, 0.50, 0.75, and 1.00 wt%) on the performance of FJF joints. The effect of raster direction on mechanical properties was examined by tensile testing of dog‐bone samples. Results showed that 0° print orientation had higher tensile strength compared to other printing directions. Shear testing of FJF joints indicated that the inclusion of graphene has enhanced the strength of 3D‐printed FJF joints by 61.18%. Fractography results showed that the formation of the shear band with the inclusion of 0.50 wt% graphene helps to distribute the stress more evenly and prevent catastrophic failure of the FJF joint. The free vibrational test revealed that the inclusion of 0.50 wt% graphene had improved the natural frequencies, as the presence of graphene‐enhanced the interfacial bonding between FJF adherend and adhesive.Highlights 0° print orientation had higher tensile strength than other printing directions. Inclusion of graphene‐enhanced the shear strength of flat‐joggle‐flat (FJF) joints by 61.18%. Shear band formation delayed the failure of graphene‐reinforced FJF joints. FJF reinforced with 0.50 wt% graphene had adherend failure. FJF joint added with 1.0 wt% graphene had lower natural frequencies.