AXIAL LOW VELOCITY IMPACT RESPONSE OF ANISOTROPIC ANTI-TETRACHIRAL FILLING LATTICES

Interest to crash response of vehicle parts is increasing closely related with their importance for safety of passengers. In low velocity crash case, integration of foams to tubular systems shows positive effect on the performance. While foams are classified stochastic micro lattice structures, recently, dynamic behaviour of lattices in macro size are being researched with 3D printing technique. In addition to conventional macro lattices showing positive Poisson's ratio have good energy absorbing capabilities, with only geometrical modification macro lattices with negative Poisson's ratio can be created and have better energy absorbing capability than conventional ones. In this study, in different dimensions, blocks of anti-tetrachiral metallic lattices exhibiting negative Poisson's ratio, are modelled. Crushing behaviour of them is investigated under low-velocity impact using explicit and implicit FEA tools. With the results of this study, suitable width-lenght ratio of macro level anisotropic anti-tetrachiral lattices will be able to classified. In addition to that, force-time behaviour in different impact velocities will be able to understood to use in not only tubular systems but also in sandwich structures as core part.