| Summary: In this study, the mechanical behaviours of 316L stainless steel micro lattice materials manufactured via selective laser melting method are aimed to investigate as experimental, numerical and theoretical. The experimental studies compose static and dynamic tests. By means of these tests, the mechanical responses and collapse behaviours of individual micro struts and lattice blocks under static and dynamic loads are investigated. It is disclosed from the experimental results that relative density and cell topology are the most significant parameter over mechanical behaviours. Also, it is found that the strain rate dependency for both individual micro struts and lattice blocks exists. In the theoretical studies, the empirical statements predicting the initial elasticity modulus and collapse stresses for micro lattice topologies are obtained using classic mechanic formulas. It is found that to take into account the geometrical effects around the micro strut junctions in the theoretical and numerical modelling gives more compatible results with experiments. In the numerical studies, the numerical models using finite element method are developed to be compatible with experimental data. Also, a series of parametric studies are fulfilled to examine the wave propagation in micro lattice structures and to determine the influence of structural disorders and boundary layers to mechanical behaviours thanks to the verified numerical model. It is determined by means of numerical studies that the wave propagation governs the mechanical behaviour of lattice structures and, in parallel to this, the micro inertia effects start to be dominant, as the impact velocity increases.
Key Words: Micro lattice Structures, Selective Laser Melting Method, Cellular Materials, Finite element method, Mechanical Properties
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