The plastic behavior in the large deflection response of slender sandwich beams with fiber metal laminate (FML) face sheets and a metal foam core under transverse loading is studied. According to a modified rigid–perfectly plastic material approximation, an analytical model is developed, and simple formulae are obtained for the large deflection response of fully clamped FML sandwich beams, considering the interaction of bending and stretching. Finite element (FE) calculations are conducted, and analytical predictions capture numerical results reasonably in the plastic stage of large deflection. The influences of metal volume fraction, strength ratio of metal to composite layer, core strength, and punch size on the plastic behavior in the large deflection response of FML sandwich beams are discussed. It is suggested that, if the structural behavior of fiber-metal laminate sandwich beams is plasticity dominated, it is similar to that of metal sandwich beams. Moreover, both metal volume fraction and the strength ratio of metal to composite layer are found to be important for the plastic behavior in the large deflection response of fiber metal laminate sandwich beams, while core strength and punch size might have little influence on it.

In this work, the dynamic behavior for clamp-supported rectangular fiber metal laminate (FML) sandwich tubes with metal foam core under low-velocity impact is studied by analytical solution and numerical method analysis. The yield criterion of the FML sandwich tube with metal foam core is proposed. Based on yield criterion, the theoretical solution for rectangular FML sandwich tubes dynamic behavior under low-velocity impact is developed considering the strength and the coupling effect of bending and tension. Finite element study is conducted. Theoretical results are well consistent in the finite element ones. Finally, the influences of material and geometric parameters, and impact position on impact force and maximum deflection of FML sandwich tubes are analyzed systematically. The results reveal that the FML sandwich tubes’ impact forces increase with the increase of the strength, number and thickness of the metal layer, the strength and thickness of the composite layer and foam strength; and impact forces increase with the decrease of the metal volume fraction of FML. Also, the impact force increases with the decrease of the distance between the impact position and the clamp-supported end.

No abstract