The face–core debonding of sandwich structures under bending will affect the overall load-bearing capacity. Fiber metal laminate (FML) sandwich composite structures with 3D woven hollow integrated core (3D core) were prepared by vacuum resin infusion method and thermal molding process. The flexural behavior of the structures was experimentally studied by a three-point bending test and investigated by evaluation of specific flexural strength, flexural rigidity, and ductility. Numerical simulation finite element models of structures with different cores under three-point bending were calculated by ABAQUS/Explicit. Results showed that plastic rotation of the “8”-shaped fibers in the 3D core was the main reason for the failure modes of asymmetric densification. FML as the faceplate of the 3D core can significantly improve its flexural strength, rigidity, and ductility.

夹层结构在弯曲下的面芯剥离会影响整体承载能力。采用真空树脂灌注法和热成型工艺制备了具有3D编织空心一体芯（3D芯）的纤维金属层压板（FML）夹层复合结构。通过三点弯曲试验对结构的弯曲行为进行了实验研究，并通过评估比抗弯强度、抗弯刚度和延展性进行了研究。采用ABAQUS/Explicit计算了三点弯曲下不同芯部结构的数值模拟有限元模型。结果表明，3D芯中“8”形纤维的塑性旋转是不对称致密化失效模式的主要原因。FML作为3D核心的面板可以显着提高其抗弯强度，