Robust numerical approaches for simulating the buckling response of 3D fiber-metal laminates under axial impact – Validation with experimental results

Abstract

The reliability and efficiency of three different numerical modeling approaches for simulating the response of a newly developed 3D fiber-metal laminate (3D-FML), subject to axial impact loading, are considered in this paper. The main objective of the study is to establish the most robust numerical framework for analyzing the performance of such complexly configured hybrid materials subject to axial impact loading in a fairly accurate, yet efficient manner. LS-DYNA finite element software is used for the purpose. The models include: (i) a full 3D solid model, where all 3D-FML constituents are modeled with 3D elements; (ii) a model with intermediate complexity, in which two different element types are used to model the metallic skins and 3D-fiberglass/foam core, respectively; and (iii) a simplified scheme, consisting of a single layer of thin-shell elements, representing all constituents of the FML. An experimental investigation is also conducted in parallel to verify the accuracy of the modeling schemes. Force and axial-shortening histories, energy absorption capacity, and overall qualitative behavior obtained numerically are compared to experimental results. Both accuracy and computation cost are considered as the performance criteria, all with the aim of providing the reader with some perspective for robust modeling of such geometrically sophisticated composites, subject to a complex loading mechanism.

Delamination Buckling and Crack Propagation Simulations in Fiber-Metal Laminates Using xFEM and Cohesive Elements

“…However, it is well-known that the Achilles' heel of all laminated composites is their relatively weaker interlaminar strength compared to their bending and axial strengths, and the 3D-FML is no exception. The likelihood of delamination initiation in such materials becomes even greater when they become subjected to a suddenly applied axial compressive loading [26][27][28]. Under such a circumstance, the metallic constituent often debonds from the core section.…”

Effect of Functionalized Graphene Nanoplatelets on the Delamination-Buckling and Delamination Propagation Resistance of 3D Fiber-Metal Laminates Under Different Loading Rates

“…Overall, the results are more consistent for the lowest and highest energies than for the two medium energies. As discussed in [6], this is attributed to the fact that 3 J and 4.5 J energies hover around the energy that corresponds to the damage threshold. Therefore, the sensitivity to the reaction of a given specimen at the onset of buckling, which is naturally volatile, is further amplified.…”

“…Each specimen category was subjected to four impact energies (1.5 J, 3 J, 4.5 J, and 7 J). The impact energies were chosen according to an experimental investigation conducted earlier by the authors [6] and are aimed to cause (i) elastic buckling; (ii) initiation of a permanent deformation; (iii) propagation of the delamination and (iv) complete failure of the specimens, respectively.…”

“…Due to the impressive specific strength, stiffness and impact absorption properties of this hybrid system, 3D-FMLs are considered as economical and effective light-weight material systems, suitable for the fabrication of transport vehicles and aircraft shell structures [3,4]. However, as highlighted in some of the authors’ previous works [5,6,7], the outstanding performance of this class of FML is somewhat compromised when the system becomes subject to in-plane loading. This is mainly due to the relatively low strength of the magnesium/FRP interface segment of this FML.…”

Static and dynamic characteristics of nano-reinforced 3D-fiber metal laminates using non-destructive techniques

“…To improve 2DFMLs and increase their overall stiffness cost-effectively, a new rendition of conventional thin 2D-FMLs was recently introduced by Asaee and Taheri [47], thereafter having been referred to as three-dimensional FLM (3DFML). This class of FMLs has been demonstrated to possess exemplary characteristics compared to conventional FRPs and 2DFMLs, especially from the perspective of resiliency against impact, as demonstrated in De Cicco and Taheri [48]. A 3DFML is essentially a sandwich composite consisting of a novel 3D fiberglass fabric (3DFGF), sandwiched between thin sheets of a lightweight metallic alloy.…”