Effect of heat treatment on fatigue behavior of as-built notched Co-Cr-Mo parts produced by Selective Laser Melting

•Study of two type of heat treatments on static and fatigue properties of unnotched and notched SLM CoCrMo.•Reduced porosity of the SLM parts in vacuum heat treatment.•Significant improvement of fatigue strength after heat treatment in presence of pressure and vacuum.•Synthesis of fatigue data for different post treatments using energy-based model. In this paper Cobalt-Chromium-Molybdenum (Co-Cr-Mo) specimens produced by Selective Laser Melting (SLM) for biomedical field were studied. In particular, fatigue tests were carried out comparing as-built condition with Hot Isostatic Pressing (HIP) and a heat treatment under vacuum condition. The influence on microstructure and fatigue properties was investigated on plain specimens and with a V-notched geometry. Both vacuum heat treatment and HIP had effects on the microstructure and internal defects, which resulted in an enhancement of quasi-static and fatigue properties. Lastly, notch sensitivity and applicability of ASED failure criterion for fatigue life prediction notched specimens were evaluated.