Dynamic response and failure mechanism characterization of composite‐metal sandwich structures under slamming impact utilizing CEL method

Slamming is a complicated fluid–structure coupling process accompanied with complex transfer of load and energy, which may pose a significant risk to the overall safety of structure. This paper aims to evaluate the dynamic response and elucidate the failure mechanism of composite‐metal sandwich structures under slamming impact. Firstly, a reliable numerical simulation process is established based on CEL method in ABAQUS/Explicit combining with a VUMAT subroutine, whose effectiveness is verified through the comparison with published experimental results. Subsequently, dynamic response of the sandwich structures is investigated considering the influence of slamming velocity and material constituent. Meanwhile, damage evolution and critical failure mechanism are assessed through progressive damage analysis. Results show that CF‐Al‐CF case owns the best mechanical performance and the latest ultimate failure moment. The overall performance of sandwich structure is mainly dependent on the mechanical properties of skin. Additionally, damage of Al‐CF‐Al case is more sensitive to the variation of velocity compared with that of CF‐Al‐CF and Al‐Al‐Al cases, which indicates that the ductility of core is responsible for ultimate damage. Moreover, extensively distributed matrix tension damage can be identified as the critical damage mode, which may further cause debonding damage and even fiber fracture. A reliable process is established for the simulation of slamming impact using CEL method; Slamming response of the sandwich structure with different constituentis is characterized; Dominate damage mode and critical failure is investigated through progressive damage analysis