Assessing the mechanical and vibrational response of hybrid metal-fibre sandwich panels fabricated with additively manufactured core structures

Composite sandwich structures are essential in aerospace, automotive, and maritime applications and offer significant benefits in aircraft performance, efficiency, and safety. The present study aimed to compare the performance of different additively manufactured core structures (honeycomb, triangular, and tri-hexagonal) in sandwich-structured composites, particularly focussing on their flatwise tensile strength, natural frequency, damping characteristics, and corrosion behavior. The flatwise tensile test revealed that the tri-hexagonal structure exhibited superior load-bearing capacity, with a maximum load of 615 N, outperforming both honeycomb and triangular structures. Corrosion studies were performed in atmospheric, industrial, and marine environments to assess the corrosion rate and polarisation resistance using potentiodynamic polarisation and Tafel-extrapolation techniques. The surface morphology of the corroded surface exposed to these environments was examined using scanning electron microscopy (SEM). Vibrational results showed that the tri-hexagonal core embedded sandwich composite demonstrated superior damping characteristics, exhibiting a damping factor of 0.1404 and a logarithmic decrement of 0.578. The present research highlights the potential of using sandwich-structured composites with additively manufactured core designs (honeycomb, triangular, and tri-hexagonal). The tri-hexagonal core exhibits exceptional performance in flatwise tensile strength, vibrational damping, and corrosion resistance, making it an ideal choice for engineering applications in the aerospace, automotive, and maritime industries, where high-performance, lightweight materials are essential.