Selective laser melting of chemical pure copper powders

The interest for additively manufactured copper parts is considerably growing in the recent years, thanks to the freedom of design of these technologies and the high thermal and electrical conductivity of copper, required in many applications. However, processing pure copper and its alloys via selective laser melting (SLM), a powder bed based additive manufacturing technique, presents a considerable number of difficulties which obstacle the industrial production. Considering actual SLM commercial machines these difficulties are mainly due to low laser absorption and elevate thermal conductivity of copper, which enhance the value of energy input required to fully melt and consolidate the material. This study aims to investigate the feasibility of producing high chemical pure copper samples by SLM process adopting a commercial machine equipped with a 200 W Yb fibre laser. Furthermore, the chemical composition and microstructure of the fabricated materials are investigated by XRD, optical and electron microscopy plus EDS.