Metal lattice structures possess a wide range of applications in the mechanical field, mainly because of their high functionality and their lightweight. Additive Manufacturing (AM) offers an incredible design freedom for topologically complex components, that before the advent of this technology were manufactured with many difficulties and expenses: world of lattices made a huge step forward thanks to AM. Different engineering disciplines employ lattices for designing components, using latest technologies. One of the most important application nowadays for these materials, especially when it comes to aerospace, biomedical and automotive sectors, is as energy absorbers: this thesis wants to be a contribution in this direction.