Advanced lightweight 316L stainless steel cellular lattice structures fabricated via selective laser melting

PublishedJournal ArticleThis paper investigates the manufacturability and performance of advanced and lightweight stainless steel cellular lattice structures fabricated via selective laser melting (SLM). A unique cell type called gyroid is designed to construct periodic lattice structures and utilise its curved cell surface as a self-supported feature which avoids the building of support structures and reduces material waste and production time. The gyroid cellular lattice structures with a wide range of volume fraction were made at different orientations, showing it can reduce the constraints in design for the SLM and provide flexibility in selecting optimal manufacturing parameters. The lattice structures with different volume fraction were well manufactured by the SLM process to exhibit a good geometric agreement with the original CAD models. The strut of the SLM-manufactured lattice structures represents a rough surface and its size is slightly higher than the designed value. When the lattice structure was positioned with half of its struts at an angle of 0° with respect to the building plane, which is considered as the worst building orientation for SLM, it was manufactured with well-defined struts and no defects or broken cells. The compression strength and modulus of the lattice structures increase with the increase in the volume fraction, and two equations based on Gibson-Ashby model have been established to predict their compression properties. © 2013 Elsevier Ltd.This work has been supported by the TSB funded project is entitled ‘SAVING – Sustainable product development via design optimisation and AdditiVe manufacturING’ and is a collaboration between the Simpleware Ltd., Delcam PLC, University of Exeter, 3T RPD, Crucible Industrial Design Ltd., EOS Electro Optical Systems Ltd. and Plunkett Associates Ltd. The characterization experiments in this study were supported by the founds of State Key Laboratory of Material Processing and Die & Mould Technology in Huazhong University of Science and Technology, China (Grant Nos. 2012-P02 and 2013-09). The authors thank Dr. Chang Hong and Dr. Wear Lesley for assistance with Micro-CT, SEM and optical microscope measurements