The Development of Design Rules for Selective Laser Melting

Abstract

The research reported in this thesis focuses on assisting the design process in respect of end use metallic products produced using the Selective Laser Melting (SLM) technology. The advancements in layer additive manufacturing technologies such as SLM have enabled the manufacture of end use products directly from Computer Aided Design data. Many companies and researchers are exploring the application of SLM in industry for specific applications, such as the mass customisation of biomedical implants and novel lattice structures. However, bridging SLM from research into mainstream manufacturing is not straightforward, as demanding industry standards and compliance need to be fulfilled. Additive Manufacturing (AM) technologies are often perceived by designers as being able to generate all conceivable geometries. However, SLM is not completely freeform as the inherent process difficulties can distort many part geometries, and designers often lack an understanding of these process issues and their effect on the final SLM product. The aim of this research is to address this lack of design knowledge, by developing a set of design rules to allow for more predictable and reliable results when manufacturing parts with SLM. This thesis documents how the design rules were created. Firstly, the geometric limitations of SLM were evaluated through a quantitative cyclic experimental methodology. Part orientation, fundamental geometries and compound design features were explored until self-supporting parts with the optimum part accuracy were achieved. Design rules were then created and evaluated through a series of interviews with industrial and academic design professionals.