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In this study, we compare the effect of various precursor‐based graphene oxide (GO) nanofillers on enhancing the mechanical performance of E‐glass fiber‐reinforced epoxy resin composites (EGFPs). GO derived from bituminous coal (BC‐GO) and graphite (Gr‐GO) were dispersed into an epoxy resin matrix. The resulting mixture was combined with E‐glass fiber mats using vacuum‐assisted resin infusion molding. Notable improvements (38.9% in flexural strength, 22.9% in tensile strength, and 21.6% in impact strength) were observed in BC‐GO‐reinforced EGFPs at 0.25 phr loading of BC‐GO. The improvements for Gr‐GO‐reinforced EGFPs were 28%, 9.3%, and 6.8%, respectively. XRD analysis of BC‐GO showed a diffraction peak at 2θ = 20.9°. Except for this peak, no other crystalline peaks were observed when BC‐GO was incorporated into EGFPs. FTIR spectra of both composite samples, with or without the nanofiller, were similar due to the spectral peaks overlap. TEM demonstrated the exfoliated morphology of BC‐GO in EGFPs. These findings underscore the potential of BC‐GO as a cost‐effective reinforcement for polymer nanocomposites across various industrial applications, including the development of lightweight and strong materials for aerospace and automotive industries, protective coatings, petroleum, and aerospace production systems. Highlights: BC‐GO demonstrates superior mechanical performance compared to Gr‐GO in EGFPs.0.25 phr BC‐GO improves 38.9% flexural, 22.9% tensile, and 21.6% impact strengths.Beyond 0.25 phr, BC‐GO and Gr‐GO showed a decline in mechanical enhancement.Role of particle size, loading & adhesion to matrix analyzed using XRD, FTIR, and DLS.Coal‐GO is an attractive alternative nanofiller for EGFPs. [ABSTRACT FROM AUTHOR]

Fiber‐metal laminates (FMLs) are attracting much attention from researchers as emerging aerospace materials. In this paper, 1060‐H112 aluminum alloy‐carbon/glass fiber laminates were prepared by vacuum bagging method. Subsequently, based on tensile, three‐point bending and low‐velocity impact experiments, the quasi‐static mechanical properties as well as the dynamic response to impact of the two fiber laminates were investigated. The results show that the carbon fiber metal laminate (CARALL) has stronger tensile strength and inter‐ply tensile consistency, while the glass fiber metal laminate (GLARE) has better bending resistance. The impact response of CARALL and GLARE is closely related to the impactor shape and impact energy. The peak loads of the FMLs increased with increasing impact energy over the range of impact energies tested. However, the peak load of CARALL is more sensitive to the impact energy, while the deformation of GLARE is more sensitive to the impact energy. With complete penetration of the impactor into the target, the fibers of GLARE were ductile fracture and fibers of CARALL were brittle fracture for the blunt impactor impact, while the fibers of both GLARE and CARALL were ductile fracture for the hemispherical impactor impact. Under the impact of both impactors, two types of FMLs showed matrix broken, delamination, and local debonding. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) woven spacer composites are competitive materials in aerospace fields due to their excellent integrated, light-weight structure. The face sheets of the 3D woven spacer composites are crucial for the mechanical properties. In this study, 3D hybrid composites, which are composed of glass and carbon fibers in the face sheets and glass fiber in the core layer as reinforcement and epoxy resin as the matrix, were designed and fabricated. The bending test results show that with the increase of the carbon fibers in the face sheets, the normalized bending strength of hybrid spacer composites showed limited improvement, while their normalized bending moduli and bending stiffnesses were significantly improved. The optical and scanning electron microscope images of the fractured surfaces reveal that the fibers in the top face sheet, which is under compression by the indenter, are damaged first and cause the failure of the entire structure, whereas the fibers in the bottom face sheets are stretched during the bending test and slightly damaged. In addition, in the failure cross-sections, pull-out of the carbon fibers is observed due to its limited interfacial bonding with the epoxy resin. This work could help optimize 3D hybrid woven spacer composite structures for better performance and lower cost. [ABSTRACT FROM AUTHOR]

The purpose of this study was to demonstrate the effectiveness of Ultraviolet (UV) prepreg fiberglass patches in repairing a damaged 4 ply fiberglass laminate. The patches used were impregnated and pre-packaged by Sunrez Corporation, and were of the "45 Biaxial" and the "2415" weave styles. Three types of specimens and two different methods of curing the patches were used for the study. The specimens measured 177.8mm × 558.8mm (7" × 22") and were made of 4 plies of prepreg fiberglass, and each prepreg patch was cured to the specimen through exposure to a 1,000 mW/cm² Starlet 300 UV light for 10 minutes. All the specimens were tested until failure with an MTS 20 kN tensile tester. The specimens with patches cured without vacuum restored an average of 39.18 kN (8808.76 lbf), 92% of the original strength of the undamaged specimens. The specimens cured while under a vacuum bag restored an average of 27.63 kN (6212.06 lbf), only 64% of the original strength of 42.98 kN (9661.55 lbf) of the undamaged specimens. The results of this study suggested that UV prepreg fiberglass patches have the potential to emerge as a high strength and easily repeatable repair method for fiberglass laminates used in aerospace applications. [ABSTRACT FROM AUTHOR]