Low‐Velocity Impact Analysis of the Woven‐Unidirectional Hybrid Composite Foam Sandwich Plate

ABSTRACT Understanding the damage evolution and energy dissipation mechanisms of lightweight composite sandwich structures contributes to improving the damage tolerance of critical components in low‐altitude aircraft. The present research proposes a woven–unidirectional hybrid carbon fiber reinforced polymer (CFRP)/PMI foam sandwich panel and systematically investigates its low‐velocity impact behavior and damage tolerance mechanisms. Experiments are conducted, and a validated finite element (FE) model is established. The synergistic effects of woven–unidirectional hybrid reinforcement architecture, interfacial properties, and foam core characteristics on impact damage evolution and energy dissipation are revealed. Woven layers promote stress dispersion through multidirectional load redistribution, while unidirectional layers provide efficient load transfer and enhanced load‐bearing capability. The coordinated deformation of hybrid face sheets, interfaces, and foam core regulates load transfer pathways and stress distribution, thereby suppressing localized damage propagation and structural failure. Furthermore, the effects of impact conditions, ply architectures, and interlaminar properties are systematically analyzed to establish a relationship with damage evolution and energy dissipation behavior. The DH‐L hybrid stacking sequence achieved a peak load of 9.0 kN and an energy absorption of 9.7 J. In addition, the minimum specific energy absorption under multipoint impact reached 0.17 kJ/kg. By adopting a reasonable hybrid design strategy, the impact response of the structure can be optimized.