Study On Mechanical Properties Of A Curved Edge Concave Multi-cell Structure With Negative Poisson’s Ratio Effect

Compared with traditional engineering materials,negative Poisson’s ratio mechanical metamaterials have many excellent mechanical properties.In this paper,a new type of variable angle and edge concave honeycomb structure with negative Poisson’s ratio effect is proposed,and a three-dimensional model structure is constructed from the two-dimensional model.In the aspect of statics,by using the energy method the equivalent Poisson’s ratio and the equivalent elastic modulus of the two-dimensional cells are acquired,and the validity of the analytical results is verified by comparing with the finite element numerical results.In this paper,the relationship between the geometrical structural parameters of two-dimensional metamaterials and the mechanical properties of materials is discussed,which provides a theoretical basis for the mechanical properties analysis and design of this kind of lightweight metamaterials.In terms of dynamics,the relative density of two-dimensional cell in this paper is theoretically calculated,and the finite element models of two-dimensional cell and three-dimensional cell are established by ABAQUS respectively.The structural deformation mode and dynamic response curves of the honeycomb structure under the impact of 7m/s,21m/s,35m/s and 70m/s velocity are given.Based on the deformation of cell material,the deformation mode of the honeycomb structure in the impact process,in the impact process the relative density change and deformation failure characteristics of the whole honeycomb structure are discussed,and the energy absorption rate and platform stress of the honeycomb material at different impact velocity are given.The relationship between radian parameters and impact velocity of cellular material and honeycomb structure deformation mode,dynamic response curve,platform stress and energy absorption rate is discussed,which provides a mechanical basis for the analysis of energy absorption effect and impact deformation failure study of this kind of lightweight metamaterials.