In Plane Mechanical Properties of Tetrachiral and Antitetrachiral Hybrid Metastructures

A novel tetrachiral and antitetrachiral hybrid metastructure is proposed, and its in-plane mechanical properties are studied through strain energy analysis. Based on rigid ring rotation assumption, the analytical expression for the in-plane modulus of anisotropic tetrachiral and antitetrachiral hybrid metastructure is derived, and in-plane tensile experimental test and finite element simulation are performed and compared with the theoretical models. The corresponding in-plane anisotropic mechanical properties can be tuned with three independent dimensionless geometrical parameters, and effects of dimensionless geometrical parameters on the in-plane mechanical properties are studied systematically. Finally, an innovative tetrachiral and antitetrachiral hybrid metastructure stent is designed, and its mechanical behaviors under uniaxial tensile loading are investigated. It is found that the designed tetrachiral and antitetrachiral hybrid stent shows negative Poisson ratio properties, and the axial and circumferential deformation can be controlled through adjusting the spacing of unit cell along axial and circumferential directions.