Compressive property of Al-based auxetic lattice structures fabricated by 3-D printing combined with investment casting

Auxetic lattice structures are a new kind of structures that show unique mechanical performance, particularly negative Poisson's ratio behavior. In the present study, an Al-based auxetic lattice structure has been fabricated by 3-D printing and investment casting, and the compressive mechanical behavior was studied. It is shown that increasing the length of re-entrant struts or re-entrant angle leads to decreased compression strength but increased Poisson's ratio. If the relative density of the structures keeps constant, the elastic modulus and compression strength will be enhanced as the Poisson's ratio increases owing to the auxetic effect.