New concept of carbon fiber reinforced composite 3D auxetic lattice structures based on stretching-dominated cells

Abstract

A new concept of 3D auxetic lattice structures with high stiffness is proposed in this paper. Correspondingly, a feasible method for rapidly fabricating the proposed structures with high-performance continuous carbon fiber reinforced polymer (CFRP) composite is exploited. Theoretical models for predicting the homogenized elastic properties of the representative structure along all principal axes, including the Young's moduli, Poisson's ratios and shear moduli, are developed. Based on the models, directional dependence of structural homogenized elastic properties is investigated in detail. The compressive elastic behaviors of the 3D auxetic lattice structures fabricated with high-performance continuous carbon fiber reinforced polymer (CFRP) composite are further investigated in a combination of numerical analysis and experiments. Our results suggest that the new concept of 3D auxetic lattice structures are very suitable for uniaxial loading and can be great candidates where excellent load-bearing capacity and obvious negative Poisson's ratio effects are simultaneously desired. Coupled with the proposed efficient fabrication process, our efforts may help to promote the 3D auxetic lattice structures to be widely used in a variety of applications.