Enhancement of buckling response of stainless steel-based 3D-fiber metal laminates reinforced with graphene nanoplatelets: Experimental and numerical assessments

This research investigates the effects of the inclusion of graphene nanoplatelets (GNPs) on the buckling response of a set of novel three-dimensional fiber metal laminates (3D-FMLs) under a uniaxial compressive load. This special 3D-FML consists of a 3D fiberglass fabric (3DFGF)-epoxy composite hybridized with basalt-epoxy laminate with their resin containing different concentrations of GNPs (0.25, 0.5, and 1.0 wt%), sandwiched between stainless steel (SS) face-sheet with different thicknesses (0.3 mm and 0.48 mm). To further enhance the response of the 3D-FMLs, the cavities of their 3D fabric are filled with two-part low- and high-density liquid polyurethane foam. The main objective is to develop a lightweight and resilient hybrid material system with a competitive cost. In addition, the response of the 3D-FMLs is simulated numerically using LS-DYNA, a commercially available finite element (FE) software. The results produced by the FE models are in good agreement with those obtained experimentally. Moreover, a parametric numerical study is carried out to assess the influence of SS thicknesses and specimen gauge lengths on the buckling response of this hybrid system. The results indicate that a combination of high-density polyurethane foam with 0.25 wt% of GNP content produces the highest buckling capacity, cost-effectively. The microstructural analysis using the field emission scanning electron microscopy (FESEM) technique would also exhibit the distribution and agglomeration of GNPs within the core of 3D-FMLs.