Selective Laser Melting of a CoCrMo alloy for biomedical applications: Correlations between microstructure and process parameters

The Co28Cr6Mo alloy is a well-established metallic biomaterial, widely used for the fabrication of orthopaedic permanent implants for joint replacement. Nowadays the manufacturing of Co28Cr6Mo medical devices is expensive and time consuming in the reason of high melting point, high hardness and low machinability of this alloy. The Additive Manufacturing (AM) technologies, such as Selective Laser Melting (SLM), allow to simplify the manufacturing route and, noteworthy, to realize customized implants based on patient-specific needs. However, many concerns remain to obtain high quality and reliable components; in particular, the relationship between the different process parameters and the final microstructure needs a deeper investigation. In the present work a wide range of process parameters have been considered for the production of SLM specimens and the corresponding final microstructure has been fully characterized. The experimental investigation allowed to define the best processing window of energy density values for producing near full-density and defect-free components.