The Perforation Resistance of Aluminum-Based Thermoplastic FMLs

Abstract

The perforation resistance of fibre metal laminates (FMLs) made of an S-glass fibre reinforced poly-ether-ketone-ketone (GF/PEKK) composite and an aluminium alloy (2024-T3) is investigated. Initial attention is focused on assessing the effect of the processing temperature on the tensile strength of the aluminium alloy. Here, it has shown that the processing cycle results in a reduction of approximately 35% in both the tensile strength and yield strength of the aluminium alloy. A comparison of the quasi-static and dynamic perforation responses of the FMLs highlighted the rate-sensitivity of these laminates, with the perforation energy increasing as the loading rate varies from quasi-static to impact. After testing, the FML specimens were sectioned to highlight the prevailing failure modes. An examination of the cross-sections indicated that the impact energy of the projectile is absorbed through plastic deformation and tearing of the metal layers, delamination between the composite plies and metal layers as well as fibre fracture. Finite element models (FEM), using ABAQUS/Explicit, have been developed to predict the behaviour of the FMLs subjected to dynamic loading. The outputs of the FE models were then validated against the measured experimental force–displacement traces and the observed failure modes. The results of the FE models were in a good agreement with the experimental data, in terms of the initial stiffness, maximum force and maximum displacement, as well as the perforation mechanisms.

A Review on Finite-Element Simulation of Fibre Metal Laminates

“…The lack of other examples does not allow one to formulate an unequivocal conclusion, and further investigation is needed in this area. Some researchers use a mixed approach and model aluminium layers as solid layers and composite layers as continuum shells [6,8]. However, the aforementioned problems affect mostly composite layers, so it does not seem to solve the eventual problem.…”

“…Numerical simulations of fibre metal laminates have been conducted for many years, and interest in them is not decreasing. Examples of current research in the field can be found for example in [5][6][7][8][9][10]. In experimental research on FMLs, a visible trend has been observed in a variety of standard configurations and materials.…”

“…The numerical simulations of fiber-metal laminates are mostly carried out as a support for experimental research, so in this section, we will summarize the most common types of tests conducted for FMLs. Due to the current field of application in aircraft fuselages and similar structures, a very common researched aspect of the experimental-numerical approach is the impact of low velocity [7,8,10,[17][18][19][20][21][22][23][24][25]. The low-velocity impact is often realized following standards, for example, ASTM D7136 [26].…”

Effect of Indenter Nose Shape and Layer Configuration on the Quasi-Static Perforation Behaviour of Metal–Plastic Laminates

“…In recent decades, there has been a growing interest in using lightweight structures with a specific energy absorption capacity and fatigue resistance in the aerospace, automotive and defence industries when the structures are subjected to impact loading. In this regard, fibre metal laminates (FMLs) composed of a number of thin metal sheets with piles of composite material (prepregs) stacked together have attracted significant attention due to their outstanding impact and fatigue properties [ 1 ]. Examples of FMLs include GLARE (glass fibre-reinforced aluminium), CARALL (carbon fibre-reinforced aluminium laminate) and ARALL (aramid fibre-reinforced aluminium laminate) [ 2 ].…”

New Advances and Future Possibilities in Forming Technology of Hybrid Metal–Polymer Composites Used in Aerospace Applications

“…Fibres used for their production can be continuous or discontinuous (staple fibres, whiskers) [41,42]. Numerous products made of single fibres, such as fabrics, mats, rovings, or preimpregnates [43,44], can also be used as reinforcement.…”