In-plane elastic properties of meta-chiral star-shaped lattice structure

A combination of chirality, anti-chirality, and re-entrant lattice pattern is proposed to form a new two-dimensional meta-structure, and a comprehensive parametric study is conducted by using experimental and numerical analysis. The proposed structure can undergo larger deformations without significant stress concentrations. Based on the verified finite element model, the effects of various geometrical parameters on the in-plane mechanical response of the structure are investigated. Results show that the thickness of the structure is the most dominant factor in affecting the Young modulus while other parameters can alter Poisson's ratio. In addition, the proposed structure exhibits tunable negative/near-zero Poisson's ratios.