Damping mechanisms of CFRP three-dimensional double-arrow-head auxetic metamaterials

Auxetic materials and structures as a class of metamaterials have been extensively studied and evaluated for many applications. This paper focuses on the vibration damping mechanisms of composite three-dimensional double-arrow-head (3D DAH) auxetic metamaterial. The composite 3D DAH auxetic structures are made from carbon fiber reinforced polymer (CFRP) using an assembly method. The damping performances of this structure is characterized by compressive loading-unloading tests and sine sweep frequency experiments. Damping parameters and energy consumptions in unit volume are analyzed synthetically to explore the contribution of various damping mechanisms. The results show that the structure consumes more energy with the strain level increase, but the augment is not large; structural hysteresis energy dissipation due to the large deformation is not related to the loading speed; the contribution of macroscopic frictional energy and elastic buckling energy consumption is much greater than that of intrinsic material damping energy dissipation. It is observed that the Poisson's ratio of such structures is approximately linear with the comprehensive evaluation factor and vibration transmissibility per unit height respectively. The comparison in the performance of conventional structure materials shows that the 3D DAH structure has excellent comprehensive characteristics of light weight, high specific strength and high damping performance.