Analysis on the effect of sodium hydroxide treatment and graphene nano‐particle reinforcement on the shear behavior and modal analysis of glass fibre reinforced polymer flat‐joggle‐flat composite joints

Abstract The use of composite materials, particularly glass fiber‐reinforced polymers (GFRP), has considerably increased. The present investigation seeks to ascertain how sodium hydroxide (NaOH) treatments and the incorporation of graphene nano‐particulates (GNP) in GFRP flat‐joggle‐flat (FJF) composite joints. The experiments demonstrated that surface treatment with 0.1 N NaOH and the addition of 0.25, 0.50, and 0.75 wt% GNP reinforcement to the resin considerably enhanced the shear behavior of the FJF joints by 5.48%, 16.04%, and 32.77%, respectively, as compared to plain GFRP specimens, due to the improved chemical bonding and excellent IR radiation retention. 0.2 N NaOH treated with the same GNP concentrations lowered the shear strength compared to 0.1 N NaOH due to the linear reduction in fiber size. Field emission scanning electron microscopy gives a clear failure analysis of the FJF joint specimens. Fourier transform infrared spectroscopy investigation determines the chemical structure of GFRP materials based on distinctive peak intensities in the infrared range and different functional groups contained in the composite materials. Atomic force microscopy testing was done to evaluate the surface textures. The vibration analysis firm that the FJF joint having 0.1 N NaOH with 0.75 wt% of graphene had the highest natural frequency. Highlights The effect of NaOH treatment and graphene influence on FJF joints. Shear analysis of the FJF composite joints. FTIR and AFM techniques were adopted to analyze the surface properties. Modal analysis is used to evaluate the natural frequencies.