Damage Characterization and Modelling of Composite Plates Subjected to High-Speed Oblique Impacts

Abstract

Simulating high-speed oblique impacts on composites remains a critical engineering challenge, as the monolithic shell models preferred in the industry often fail to accurately reproduce the diverse failure mechanisms typical of composite materials, such as fibre failure and delamination, whose interplay with inertial effects is essential for an accurate modeling of the event. To address this, a discretized modeling approach was developed with the explicit finite element software LS-Dyna, representing a composite laminate as a stack of shell elements connected via tiebreak contacts to allow for inter-laminar failure via a purely strength-based criterion. Validation against experimental data revealed that the plate response was governed by the mutual interaction of delamination, inter-ply friction and impactor kinematics. Using maximum out-of-plane intrusion as a benchmark, the newly developed model showed a discrepancy with the test data of -2.9%, against the +17.7% of the monolithic model baseline provided by the company at the beginning of the project. Furthermore, great qualitative correlation has been observed w.r.t. the delamination morphology when compared with C-scans of the tested samples. This study demonstrates that high-fidelity prediction of both intrusion and delamination shape and size in the proposed high-speed oblique impact event can be obtained through a strength-based discretized framework without the need for complex energy parameters or computationally expensive solid elements, offering a robust and efficient solution for industrial safety analysis.