3D-printed pure copper. Density and thermal treatments effects

In the field of Additive Manufacturing (AM), interest in the production of pure copper parts is growing. The excellent thermal and electrical properties of this material make it irreplaceable in many industrial and scientific applications. Combining these aspects with the advantages provided by AM in terms of design and geometry optimization, the application potential is believed to be very broad. Notwithstanding the growing request of this kind of components, their processability via Selective Laser Melting (SLM) technology is still challenging due to the high reflectivity of copper at the emission wavelength of the conventional SLM laser sources (1064 nm) along with the thermal issues resulted from copper’s high conductivity. Considering the relevance of physical and mechanical properties in the design, this work aims to verify the quality, in terms of microstructure/density, chemical and mechanical characteristics, of the pure copper parts produced via a standard SLM machine and the effect of post-processing thermal treatments on these features. The results of this study confirm the possibility to achieve a sufficiently high density and to improve mechanical properties with appropriate heat treatments. This aspect is crucial in the perspective of understanding the current readiness level of the AM technology and the process parameters to be set in order to properly obtain copper’s properties for the desired thermomechanical performances.