Investigation of the Selective Laser Melting process with tungsten metal powder

Selective Laser Melting (SLM) is a leading Additive Manufacturing (AM) technology used for high value low volume manufacturing. It is currently used commercially for processing of steels, titanium, nickel- and aluminum-alloys in medical and aerospace industries. It is not used currently for refractory metals, mainly because of the intrinsic problems of processing higher melting point materials but also due to the process being driven slowly by the industries involved. Successful SLM processing requires development of material specific processing parameters that differ between materials and so the system must be developed to match each material used. In this study, processing of tungsten is considered for the production of solid and porous parts. The study also considers the role of the pure tungsten powder interaction with processing conditions within SLM. The process quality is quantified in terms of porosity, integrity and microstructure. The reasons why the parameters used have the effects observed is discussed and the effects on future development of this technology in this field is discussed