In this work, a numerically hybrid model is presented for the lattice structures to reduce the computational cost of the simulations. This approach consists of utilization of solid elements for the junctions and beam elements for the microbeams connecting the corresponding junctions to each other. To take into account the geometric defects, for each microbeam of the lattice structures, an ellipse is fitted to capture the effect of shape variation and roughness. Having the parameters of the ellipses, the lattice structures are constructed in Spaceclaim (ANSYS) using the geometrical hybrid approach. When the global response of the structure is linear, the results from the hybrid models are in good agreement with the ones from the 3D models. However, the hybrid models have difficulty to converge when the effect of large deformation and local plasticity are considerable in the BCCZ structures. For BCCZ lattice structures, the results are not affected by the junction’s size. This is also valid for BCC lattice structures as long as the ratio of the junction’s size to the diameter of the microbeams is greater than 2.

Lattice structures are widely used in various applications, especially in aeronautic, aerospace, and medical applications because of their suitable properties. Thanks to advancement of the additive manufacturing technology, the lattice structures can be manufactured by different methods such as laser beam melting technology. However, the presence of geometric defects in the lattice structures is inevitable due to the manufacturing process. The geometric defects may have high impact on the mechanical strength of the structures. The geometric defects are directly linked to the process parameters. This paper presents the analysis of the correlation between the process parameters and the mechanical strengths. In addition, the uncertainty propagation of the mechanical strengths according to the process parameters is also studied.

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