Rapid Product Development Association of South Africa
Selective Laser Melting, titanium, fatigue
Additive manufacturing has of late gained a lot of attention; this is partly because light weight metallic components can be produced directly from 3D CAD data. Selective laser melting (SLM) is a promising additive manufacturing technique as it can provide metallic components with complex geometries as a near net shape. However, process induced imperfections need to be considered for future applications. Although the mechanical properties of SLM produced Ti6Al4V are fairly well understood, the fracture toughness and crack propagation properties are still being researched. This paper analyses the fracture toughness and fatigue crack propagation of SLM specimens produced from Ti6Al4V powder particles. The main objective of this study is to gain insight into the effect that building direction (and specimen orientation) and post processing treatments have on the dynamic behaviour of SLM Ti6Al4V components. Three specimen orientations were investigated as well as two different heat treatments that were performed on selected specimens. Post manufacture density measurements showed a density above 99,4 % for all specimens. Fracture toughness (K1c) values and fatigue crack growth Paris parameters were derived from fatigue tests. The results indicate that there is a strong influence of post manufacturing conditions as well as specimen orientation on the dynamic behaviour of SLM produced Ti6Al4V.