Experimental and simulation of quasi-static indentation loading and low-velocity impact on reinforced fiber metal laminates

Investigation and analysis of the dynamic behavior of fiber metal laminates (FMLs) and their failure resistance are essential. FMLs are presented for low density, high strength-to-weight ratio, and excellent damage tolerance for using in engineering applications. This study aims to reduce the weight of FML panels and increase the specific energy absorption through cold roll bonding (CRB), and nanoparticles (NPs) <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mi>A</mml:mi> <mml:msub> <mml:mi>L</mml:mi> <mml:mn>2</mml:mn> </mml:msub> <mml:msub> <mml:mi>O</mml:mi> <mml:mn>3</mml:mn> </mml:msub> </mml:mrow> </mml:math> . In this investigation, the experimental tests and numerical simulations are conducted on reinforced FMLs. The tests are performed to analyze the behavior of the FMLs under quasi-static indentation (QSI) and low-velocity impact (LVI). The experimental process utilized an instrumented drop-weight impact tower and a universal testing machine. For numerical simulation, the ABAQUS/Explicit software is used. The specimens are classified into three groups and three types. In quasi-static indentation tests, the SEA values for G-1 samples ranged from 1092 J/kg to 1137 J/kg, which exceeded from G-2 between 578 J/kg to 836 J/kg and from G-3 between 419 J/kg to 758 J/kg. On the other hand, in low-velocity impact tests, the SEA values for G-1 samples ranged from 142 to 143 J/kg under 26 J impact energy, from 263 to 273 J/kg based on 50 J impact energy, and from 402 to 403 J/kg according 74 J impact energy. The SEA values for G-2 samples ranged from 220 to 221 J/Kg, from 421 to 422 J/kg and 629 J/kg under 26 J, 50 J, and 74 J impact energy, respectively. Entirely, the stiffened FMLs with NPs and CRBed process have lower internal energy absorption and less face-sheet displacement. This highlights the significance of design for different applications, particularly in cases where minimal back-face deformation is crucial. Conversely, FMLs made with pure aluminum absorb more internal energy, as well as further displacement of the face-sheet, due to its deformability. The interaction between aluminum face-sheet and fiber is a critical factor in determining the mechanical properties of composite material. Carbon fiber enhances more energy absorption and leads to higher deformation, while hybrid fibers have the opposite effect. The results highlight that the specific energy absorption (SEA) under quasi-static indentation and low-velocity impact are different due to the influenced by both the loading rate and the structural configuration of the metallic layers. These findings underline the importance of the material behavior for applications in dynamically loaded structures.