Low-velocity impact and post-impact compression properties of carbon/glass hybrid yacht composite materials

In the field of maritime engineering, low-velocity impact (1-10 ms−1) is typically regarded as a quasi-static event. During navigation, yachts are inevitably subjected to low-velocity impact from floating objects in the water, and may also encounter compression after low-velocity impact. This study employs a combined approach of numerical simulation and experimental testing, aiming to investigate the damage and failure mechanisms of yacht composite laminates under conditions of low-velocity impact and post-impact compression (CAI), and by SEM and ultrasonic C-scanning the damage characteristics of different layup samples was studied in impact and compression tests. In order to conduct a more in-depth study on the damage evolution and failure mechanisms of yacht composite laminates, a three-dimensional damage model is established based on the continuum damage mechanics, and a physico-mechanical failure criterion combining the 3D Hashin and Puck criteria is employed. This criterion is used to capture the initiation points of damage in both fibers and matrix. Additionally, a bi-linear damage constitutive relationship is utilized to describe the damage evolution. Interlayer delamination is addressed through simulating the bonding behavior of interfaces. The numerical results show good correlation with the experimental results, which validates the effectiveness and rationality of the proposed numerical model. The study shows that laying carbon fiber cloth in the middle of the sample exhibits excellent impact resistance; laying carbon fiber cloth at the bottom exhibits better deformation resistance and stronger residual compression performance. Considering the three aspects of deformation, residual strength, and damage area, laying carbon fiber cloth in the first layer exhibits better mechanical properties, which provides useful reference for the design and manufacture of yacht materials and helps to improve the safety and reliability of yachts.