In sandwich composites, interfacial bonding between face sheets and core has to be strengthened to prevent debonding. In this work, sandwich composites with polyurethane core and glass fiber reinforced epoxy face sheets were prepared by vacuum infusion process. Chopped fibers of glass, carbon, and kevlar with length 12 mm were introduced between core and face sheets during fabrication in order to improve face-core bonding. The influence of chopped fibers is investigated by testing flexural, compressive, shear, and fracture toughness properties of prepared specimens according to ASTM standards. Sandwich specimens with chopped glass fibers exhibited, superior interfacial bonding between the face and the core and hence improved the mechanical properties of sandwich composite. The chopped glass fiber embedded sandwich composite has an increased flexural strength of 32.77% and compressive strength of 21.43% when compared with plain sandwich composite. In addition, the shear strength and fracture toughness behavior of specimens with chopped glass fibers are superior when compared to other chopped fibers incorporated in the interfacial region. The interfacial region between skin and core was investigated using scanning electron microscopy (SEM). Chopped glass fibers in the interfacial region showed better adhesion property along with the epoxy.

This research focuses on the mechanical and thermal characterization of vacuum-assisted resin transfer moulded epoxy-based glass fiber-reinforced composites. Mechanical testing, including tensile and flexural tests, and heat dissipation analysis under the applied load, are used to analyse the prepared specimens. A thermal imaging camera is used to measure temperature changes to determine energy release, which significantly impacts the composite's surface energy in terms of heat. Differential scanning calorimetry and thermogravimetric analysis were used to examine the thermal stability and decomposition properties. It is noted that the glass transition temperature is 371.15°C, and the decomposition temperature is 380.90°C. Under a scanning electron microscope, the fractured specimens are examined for failure analysis. According to these results, the manufactured composite is suitable for various structural engineering applications.

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Fibre metal laminates (FML) play a significant role in the aircraft industry. The present work is to achieve a high load bearing structure and wear resistant FML for airbus cargo floors and doors. An innovative attempt has been made to reveal the mechanical and tribological properties of the FML (Glass/AZ91D/Glass). The glass fibre used is of bi-diagonal fabric to enhance the shear properties of the FML. The laminates were prepared by hand layup technique, which was post compressed to a uniform shape in the compression moulding machine. Mechanical tests such as tensile, flexural, and low-velocity impact were conducted on the FML samples. The mechanical properties of the magnesium-based FML exhibit an excellent tensile strength of 227.3 MPa, the flexural strength of 231.3 MPa, and the energy absorbed by the plate are 93.648 J. These results were promising, and comparatively better than the conventional laminates in the case of load bearing structures. The wear was tested in Pin-on-Disc and the wear resistance was also found to be better than conventional laminates. The micro-structural analysis along the wear regime shows a prominent wear resistance and fewer cracks, due to the presence of AZ91D in the laminates.