Low-velocity impact response of fiberglass/magnesium FMLs with a new 3D fiberglass fabric

The main objective of the present study is to introduce a new fiber metal laminate (FML), formed by sandwiching a 3D fiberglass fabric in between thin sheets of magnesium alloy. In particular, the low-velocity impact (LVI) response and failure modes of this new FML composite are investigated experimentally and computationally. In addition, to gain a more comprehensive understanding of the response of the FML, its performance is compared against those of conventional FMLs, made with various layers of biaxial woven fabrics in place of the 3D fabric. The failure modes of the specimens are characterized based on the quantitative measurements of shape, type, and extent of damage on the FMLs’ constituents. The impact characteristics of all panels are further examined by characterizing and comparing their energy absorption capacity, residual deformation and maximum deformation due to LVI. The characteristics of the new 3D glass fabric are specifically discussed, and its positive attributes and limitations, in comparison to woven fabrics, are highlighted. The results would reveal that FML made by the 3D fabric exhibits outstanding impact absorption capacity; however, their impact energy resistance is lower than FMLs formed by woven fabrics. Moreover, as a major part of this study, a finite element analysis (FEA) framework is constructed, using the commercial finite element code ABAQUS, in order to simulate the response of such complex structures. Good agreement between the experimental and computational results demonstrate that the simulation framework can be further used to optimize the configuration of FMLs for different loading situations.