Tailoring structure of inclusion with strain-induced closure to reduce Poisson's ratio of composite materials

Abstract

Tailoring structure of inclusion with strain-induced closure to reduce Poisson's ratio of composite materials A novel 3D continuum shell structure is introduced as inclusion for composite materials with special mechanical properties in this paper. Its geometry is based on a hollow re-entrant tetrahedron. In a composite, such an inclusion can demonstrate a closure effect induced by external compression. Its specific deformation mechanism results in a special character of deformation and affects effective (global) mechanical properties of the composite. A finite-element method is used to explore quantitatively and qualitatively the deformation mechanism of the suggested inclusion and its effect on the overall mechanical performance of the composite. In this study, geometrical features of the inclusion are used as parameters. The obtained results demonstrate that this kind of inclusion could reduce the composite's Poisson's ratio; moreover, its magnitude is adjustable by changing geometrical parameters of the inclusion. Besides, an overall hardening effect is achieved for the composite, with the magnitude of global stiffness also significantly affected by geometrical features of the inclusion. Thus, the developed inclusion actually provides a potential to develop new composites with a tunable Poisson's ratio and enhanced mechanical properties .V

Experimental and numerical analysis of a novel three-dimensional auxetic metamaterial

“…In Krödel et al's work, a new design concept for small‐scale lattice materials was proposed, whose effective static and dynamic elastic properties can be controlled relatively independently through careful unit‐cell architecture . In addition, a novel 3D continuum shell structure was introduced as inclusion for composite materials with special mechanical properties by Hou et al . Ge et al reported a new NPR 3D fabric structure for composite reinforcement .…”

A novel 3D composite structure with tunable Poisson's ratio and stiffness

“…This study introduces a novel composite structure, which is developed on the basis of a stack of 3D hollow shell inclusions. The concept of the inclusion was introduced in our previous work . However, only a single inclusion was analysed in that study regarding its effects on a composite structure under compressive loading.…”

“…The geometry features of the re‐entrant hollow shell inclusions used in the developed composite structure were introduced in our previous work (Fig. ) . To analyse the effects of geometry features of this sort of inclusion, the re‐entrant degree, which is controlled by H , is used as an effective parameter (Fig.…”

“…Due to the fact that the changes in Poisson's ratio are determined by the deformation of the specific structures, such as re‐entrant honeycomb structure, chiral structure, star‐shape structure and rotating units , they cannot be treated as a solid engineering material. Additionally, these structures are hardly used as a component in a solid composite structure, since additional constraints from matrix interrupt the desired deformations of those structures .…”

Finite Element Analysis of Three-Dimensional (3D) Auxetic Textile Composite under Compression

“…Yet, plenty of reinforcements have been proposed or developed to fabricate auxetic composites, such as specific two-dimensional (2D) triangle inclusions [13,14,15], three-dimensional (3D) tetrahedron hollow shell [16,17], cellular honeycomb structure [18,19], double arrowhead [20,21], and chiral network [22]. Hou et al [14,15,16,17] found that the mechanical properties and deformation behavior of auxetic composites can be tailored by controlling the geometry features and the density of inclusions, and these findings were confirmed by Wang et al [6], Hu [13], and Li et al [18]. Recently, Bruggi et al theoretically investigated the synthesis of auxetic structures by a topology optimization approach for micropolar materials.…”