All-composite integrated 3D-Kagome lattice cores sandwich structure with flexible mortise-tenon joints

Abstract

Composite lattice cores sandwich structures have shown obvious advantages in specific mechanical property and potential multifunctional integration. 3D-Kagome lattice core is regarded as a classic core configuration with relative optimal theoretical performance. However, it is still unavailable due to preparation problem of the overlap joint-node of composite cores. In this paper, a self-locking mortise-tenon joint method is presented to sucessfully fabricate the integrated 3D-Kagome cores with the expected mechanical properties. The out-of-plane compressive behaviour and energy absorption characteristics are experimentally studied. For the composite structures with various relative densities, three kinds of compressive curves are observed, following by different failure modes. An obvious bearing reinforcement emerges for the lattice cores with high relative density. As the length-to-thickness ratio of the core-rods increases, the initial peak strength and modulus of structures both decrease with a slowing rate. Though the mortises weaken the load-bearing capacity of core-rods, the active constraint of mortise-tenon joint suppresses an obvious degradation. The dominated failure more depends on the core-height than rod-thickness. The composite 3D-Kagome cores show more excellent mechanical properties than other similar structures, especially for the elastic strain before the initial peak stress. The semi-rigid power-wasting mortise-tenon joint and load-bearing characteristics of Kagome core together provide a large deformation tolerance at a relatively high stress level. All suggest that the presented 3D-Kagome lattice cores could be considered as a potential energy absorbing material.

Improved compressive performance of lattice truss core sandwich composites with modified Kagome topologies: An experimental and numerical study

“…7 The truss core of LTCSC panels can be constructed using either fabric or yarn. Interlocking, 8 snap-fitting, 1 and hot-press molding 9 are common fabrication techniques for constructing the truss core using fabrics. First, fiber-reinforced polymer sheets are cut in accordance with a specific pattern and subsequently assembled to build the lattice truss core.…”

“…[10][11][12] The LTCSCs made of yarn exhibit a higher resistance to core-skin debonding, while LTCSCs made of fabrics have superior performance. 13 Xie et al 8 employed mortise-tenon joint design to fabricate LTCSC samples with the aim of solving the intersection connection of truss struts. Two types of failure mode was observed under flatwise compression tests: joint-node fracture and strut buckling.…”

Tunable Multifunctional Metamaterial Sandwich Panel with Quasi‐Zero Stiffness Lattice Cores: Load‐Bearing, Energy Absorption, and Vibration Isolation

“…Here, we demonstrate a novel tunable multifunctional mechanical metamaterial, also known as metamaterial sandwich panels. Unlike previously reported sandwich panels, [33][34][35][36][37][38] we start with designing kirigami-style surfaces to generate the face sheets of the metamaterial sandwich panel, which allow for stretching to achieve overall structural adjustability (see Figure 1a). Then, a quasi-zero stiffness (QZS) lattice core (see Figure 1b) is introduced to generate the lattice core of metamaterial sandwich panels, which provides the basis for achieving multifunctional properties, i.e., load-bearing, energy absorption, and low-frequency vibration isolation properties.…”

Study on damage failure for a new double-triangular truss core sandwich structure

“…At the beginning of the 21st century, the concept of dotted sandwich structure was introduced by the western material science community, led by Prof. Evans and others [ 4 , 5 ]. As people began to study truss core structures, various topological configurations such as pyramids [ 6 ], tetrahedra [ 7 ], and Kagome [ 8 ] gradually emerged. Due to the large distance between the upper and lower panels of the truss core sandwich structure, the specific stiffness and specific strength of the truss core sandwich structure are much greater than other forms of sandwich structures.…”