Development of Multiscale E‐Glass Fiber/Epoxy Composite Containing <scp>NiO</scp> @Graphene Oxide Nanohybrid: Mechanical Property Evaluation

ABSTRACT This work was carried out to assess the influence of NiO‐decorated graphene oxide (NiO@GO) on both the flexural response and dry‐sliding characteristics of E‐glass fiber/epoxy (GF/EP) composite. Initially, the surface of GO was decorated with NiO nanoparticles, and the successful synthesis of NiO@GO nanohybrids was later verified using a range of characterization routes, including X‐ray diffraction (XRD), atomic‐force microscopy (AFM), energy dispersive X‐ray spectroscopy (EDS), and X‐ray mapping. In the subsequent stage, multiscale GF/EP composites were prepared by adding various loadings of the NiO@GO nanohybrids to the matrix (0.05, 0.1, 0.3, 0.5, and 0.7 wt.%). These composites were then examined through three‐point bending and dry‐sliding wear tests. According to the results, the best flexural properties were achieved in the specimens with 0.1 wt.% NiO@GO, whereas the most favorable wear resistance appeared in those having 0.3 wt.%. By adding 0.1 wt.% of the NiO@GO nanohybrid, the flexural strength and flexural modulus of the specimen were increased by 38.8% and 19.9%, respectively, compared to the NiO@GO‐free control composite. Besides, incorporating 0.3 wt.% of the NiO@GO led to reductions of 55.2% in wear rate and a 30.3% in the friction coefficient with respect to the neat GF/EP specimen. The results of this study also confirmed the superiority of the NiO@GO nanohybrids over pristine GO for improving the mechanical performance of the GF/EP composites. Field‐emission scanning electron microscopy (FESEM) images verified that the observed improvements were primarily as a result of the improved bonding between the GF and matrix when NiO@GO nanohybrids are present.