A sinusoidal beam lattice structure with negative Poisson?s ratio property

In this study, a three-dimensional (3D) beam lattice structure (BLS) with negative Poisson's ratio (NPR) effect is proposed by applying sinusoid-shaped beams. The finite element model of the BLS is established, and its sample is manufactured through selective laser sintering (SLS) technology. The axial compression experiment and simulation are performed to investigate the compression characteristics of BLS. BLS bends to one side in the later stages of compression. It can be concluded that the BLS possess strong NPR effect and excellent energy absorption performance. In addition, the effects of compression direction, amplitude and wavenumber on the compression characteristics of BLS are further analyzed. These BLSs exhibit significant anisotropic features, and they often show the deformation modes of S-and <-shaped. When the loading directions are z-and y-axes, these BLSs have more obvious NPR effect and better energy absorption characteristics compared with those of the x-axis. In addition, it is also found that the minimum values of PR (MPR) of these BLSs often appear in the initial stages of compression, and the maximum values of Poisson's ratio (PR) usually appear around the end of compression. In summary, the BLS has excellent mechanical properties and broad application prospects.(c) 2023 Elsevier Masson SAS. All rights reserved.