Researchers at Uppsala University, in collaboration with Swedish graphene materials company Graphmatech, demonstrated a potential breakthrough in the printability of copper for laser additive manufacturing (AM). The discovery significantly lowers copper powder’s reflectivity to achieve denser printed parts.
Professor Ulf Jansson’s research group at Ångström Laboratory, Uppsala University, has carried the project to its conclusion. PhD student Simon Tidén recently won a poster prize at the Swedish Arena for Additive Manufacturing of Metals Conference for the work.
Metal AM experienced a rapid uptake across a range of industries due to its ability to produce customized and complex designs on demand. It also offers more sustainable manufacturing solutions with reduced waste and lower material requirements.
Some metals, including pure copper, are challenging due to their high reflectivity. The wavelengths commonly used in laser powder bed fusion (the dominant technology in metal AM) are deflected by the copper powder. Only a small part of the energy is absorbed by the material, which causes low density in printed parts.
Graphene technology offers a solution. Graphmatech CEO, Dr. Mamoun Taher, explained that by: “modifying the surface of the copper powder using Graphmatech’s patented graphene technology, we successfully reduced the reflectance by up to 67%.” The graphene used in this process was incorporated into the copper. The added graphene positively impact the density of the printed copper-graphene parts, thus significantly reducing their porosity.
Graphmatech’s technology coats the copper powder, thus allowing the energy wavelengths to absorb into the material. The coating is dissolved into the powder. It fuses to the copper during printing.
Graphmatech is now scaling up this technology after having made significant advances in other AM graphene-metal composites and coated powders with project partners. Graphene’s growing potential for enhanced powder processing and stronger properties in printed parts.
Professor Jansson indicated that “the new process developed to coat metal powder with graphene opens up very interesting perspectives for the design of new materials in various applications.”
“This 3D printable hybrid material has the potential to add value in a range of sectors such as e-mobility, electronics and defence,” added Dr Taher.