Simulation and Experimental Analyses on Quasi-Static and Dynamic Performances of Four-Star Cellular Structure

A novel four-star cellular structure (FSCS) is proposed. Firstly, relative density of FSCS, regular octagons and regular hexagons are obtained accordingly. Then, their in-plane quasi-static and dynamic performances are conducted under the premise of equal number of cells, equal mass and equal relative density by adopting Hyperworks and Ls-Dyna software. Macroscopic deformation processes indicate that FSCS, regular octagons and regular hexagons are presented as "compression -shrinkage" negative Poisson's ratio deformation mode, "V" deformation mode and "X" deformation mode, respectively. Subsequently, size effects of unit cell are carried out, and as the number of cell layers reaches no less than 9, platform stress of FSCS gradually tends to be stable. To verify the accuracy of finite element (FE) simulation models, quasi-static compression test is executed on three-dimensional FSCS. The results indicate that FE simulation results agree well with experimental predictions, and the proposed FSCS is equipped with superior energy absorption capability.