Prediction of Compressive Behavior of Polymer Lattice Structure by Numerical Material Testing

In this study, a numerical material testing approach is proposed to evaluate the macroscopic mechanical properties of polymer lattice structures fabricated by additive manufacturing. The proposed method introduces a novel formulation of periodic boundary conditions that accounts for inter-cell contact, enabling virtual tests under various loading directions including vertical compression, shear, and off-axis conditions. Four different lattice topologies are analyzed under each loading condition, and the results are compared with those obtained from detailed finite element models comprising multiple unit cells. Numerical results demonstrate that the proposed method can accurately reproduce the macroscopic stress-strain behavior prior to buckling. Furthermore, by applying the method to off-axis loading conditions, it is confirmed that the characteristic mechanical anisotropy of lattice geometry is appropriately captured.