Design of internal branch support structures for selective laser melting

Abstract

Purpose Selective laser melting (SLM) enables the fabrication of lightweight and complex metallic structures. Support structures are required in the SLM process to successfully produce parts. Supports are typically lattice structures, which cost much time and material to manufacture. Besides, the manufacturability of these supports is undesirable, which may impact the quality of parts or even fail the process. The purpose of this paper is to investigate the efficiency and mechanical properties of advanced internal branch support structures for SLM. Design/methodology/approach The theoretic weight of a branch support and a lattice support of the same plane were calculated and compared. A group of standard candidates of branch support structures were manufactured by SLM. The weight and scanning time of specimens with different design parameters were compared. Then, these samples were tested using an MTS Insight 30 compression testing machine to study the influence of different support parameters on mechanical strength of the support structures. Findings The results show that branch type supports can save material, energy and time used needed for their construction. The yield strength of the branch increases with the branch diameter and inclined branch angle in general. Furthermore, branch supports have a higher strength than traditional lattice supports. Originality/value To the best of the authors’ knowledge, this is the first work investigating production efficiency and mechanical properties of branch support structures for SLM. The findings in this work are valuable for development of advanced optimal designs of efficient support structures for SLM process.