A novel auxetic chiral lattice composite: Experimental and numerical study

• Published in: Composite structures Vol. 282; p. 115043
• Main Authors: Zhang, Xue Gang, Ren, Xin, Jiang, Wei, Zhang, Xiang Yu, Luo, Chen, Zhang, Yi, Xie, Yi Min
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.02.2022
• Subjects: Auxetic lattices; Chiral; Composites; Energy absorption; Negative Poisson’s ratio; Stiffness; Negative Poisson’s ratio; Composites; Stiffness; Auxetic lattices; Energy absorption; Chiral
• ISSN: 0263-8223; 1879-1085
• DOI: 10.1016/j.compstruct.2021.115043

•A novel auxetic chiral lattice composite is proposed by designing joints of the reinforcement phase.•The mechanical properties and deformation characteristics of four specimens are investigated under uniaxial compression.•The novel auxetic chiral lattice composite exhibits an enhanced stiffness and SEA capacity.•The effects of geometrical parameters and volume fraction of the reinforcement phase on the novel auxetic composites are investigated. Auxetic materials and structures have many potential applications due to their counter-intuitive deformation behavior and desirable mechanical properties. However, auxetic structures have some drawbacks, such as relatively low stiffness and stability. To improve their mechanical performance, one common method is to fill soft materials in auxetic frames, i.e., auxetic two-phase composites. In this paper, a novel method to further enhance the mechanical properties of auxetic composites has been proposed, which is implemented by designing joints of frames. Mechanical properties and deformation characteristics of these novel composites and their conventional counterparts are investigated experimentally and numerically. The results of finite element analysis and experiments exhibit a good agreement. The energy absorption capacity and auxeticity of the proposed composites could be enhanced by optimizing the design of joints. Subsequently, parametrical studies are conducted to quantify the effects of the geometrical parameters and the volume fraction of the frame.