Characterization of Lattice Structures for Additive Manufacturing of Lightweight Mechanical Components

Abstract

Tensile and compression test specimens comprising lattice structures with simple cubic, crossing-rod and body-centered cubic (BCC) unit cells are produced via SLM additive manufacturing (AM) of AISI 316L stainless steel and CoCr powder. Equivalent stress-elongation curves are obtained, with equivalent strength, specific strength, stiffness modulus and specific stiffness calculated based on specimen density and sample cross-section. The obtained results highlight the fact that analogous structures can behave very differently depending on the chosen material. While large differences are obtained in strength and stiffness between the different unit cell types, specific strength and specific stiffness vary to a lesser extent. Two case studies are presented, including a porous structure suitable for bone implants in the field of biomedical engineering and an AISI 316L food packaging machine component. The results obtained in this study provide useful guidelines and equivalent properties for designers wishing to exploit the advantages of internal lattice structures in AM.