Fatigue performance evaluation of selective laser melted Ti-6Al-4V

Additive Manufacturing of titanium components holds promise to deliver benefits such as reduced cost, weight and carbon emissions during both manufacture and use. To capitalize on these benefits, it must be shown that the mechanical performance of parts produced by Additive Manufacturing can meet design requirements that are typically based on wrought material performance properties. Of particular concern for safety critical structures are the fatigue properties of parts produced by Additive Manufacturing. This research evaluates the fatigue properties of Ti-6Al-4V specimens produced by the Selective Laser Melting additive manufacturing process. It was found that the fatigue life is significantly lower compared to wrought material. This reduction in fatigue performance was attributed to a variety of issues, such as microstructure, porosity, surface finish and residual stress. There was also found to be a high degree of anisotropy in the fatigue performance associated with the specimen build orientation.