Modeling of cellular structures under static and fatigue loads

Lightweight structures based on lattice geometries are promising in multifunctional design of mechanical components. In fact they allow for the integration of different properties as lightness, impact energy absorption, thermal exchange and others. The modeling of lattice structures is generally complicated by the intrinsic geometrical shapes and specific methodologies that are needed to obtain reliable predictions in short time. To design this kind of structures, topology optimization can be considered in order to find a preliminary configuration. However, the optimized pseudo-density field is often characterized by intermediate values over some regions. In this case, a suitable lattice material can be used to infill such regions by meeting the overall mass and equivalent elastic properties that can be assessed by a pertinent homogenization method (static load cases). In case of alternate loads, the same approach is used, followed by de-homogenization (or inverse homogenization) to determine the maximum stress levels on the most critical regions of the structure.