High‐velocity impact response and damage behavior of bio‐inspired helicoidal composite laminates: Experimental and numerical investigation

Abstract Bio‐inspired helicoidal composite laminates have been found to have better impact resistance and energy absorption than conventional laminates. To study the impact responses and damage behaviors of bio‐inspired helicoidal composite laminates under high‐velocity impact, the composite laminates with three helix angles were designed and tested. Two types of light‐gas gun were used to provide low and high impact energies, the velocity was measured using a velocimeter and the damage to the laminate profile was observed by scanning electron microscopy. Numerical simulation is then used to simulate the damage behavior of the helicoidal laminates based on the Hashin failure criterion and the revised dynamic increase factor. The results show that: under an impact of low energies, the helicoidal mechanism serves to absorb the impact energy through the generation of additional delamination. The laminates with the helix angle of 15° exhibits the maximum delamination area and the minimum residual velocity. However, under the impact of higher energies, the helicoidal mechanism is unlikely to improve the energy absorption and will inhibit the delamination damage. The laminates with the helix angle of 45° have the greatest inhibitory effects on delamination damage, with a delamination area reduction of 35.41%. Due to these differences, therefore, the use of helicoidal laminates should be more cautious in high‐velocity impact resistance and better avoid high‐energy situations. These findings can support the design of novel impact resistance structures. Highlights High‐velocity impact tests and FEM simulation of helicoidal laminates are carried out Damage behaviors and failure mechanism of helicoidal laminates are studied Delamination and fiber breakage are the main failure modes The laminates with the helix angle of 15° has the best impact resistance.