Researchers at Uppsala University, Sweden, in collaboration with Graphmatech, also based in Uppsala, have demonstrated a potential breakthrough in the use of copper in Laser Beam Powder Bed Fusion Additive Manufacturing (PBF-LB), said to significantly lower the reflectivity of copper powder to achieve denser AM parts.
In the Additive Manufacturing process, some metals, including pure copper, can present a challenge due to their high reflectivity. At the wavelengths commonly used in PBF-LB process, only a small part of the energy is said to be absorbed by the material, which can result in low-density parts.
To overcome the challenges in PBF-LB processing of pure copper, the researchers have identified graphene technology as a solution. “By modifying the surface of the copper powder using Graphmatech’s patented graphene technology, we successfully reduced the reflectance by up to 67%,” stated Dr Mamoun Taher, Graphmatech’s CEO.
The graphene was also reported to survive the build process, positively affecting the density of the as-built copper-graphene parts by significantly reducing porosity.
The research is being undertaken by Professor Ulf Jansson’s research group at Angstrom Laboratory, Uppsala University, with PhD student Simon Tiden having recently been awarded a poster prize at the Swedish Arena for Additive Manufacturing of Metals Conference for the work.
“The new process developed to coat metal powder with graphene opens up very interesting perspectives for the design of new materials in various applications,” stated Professor Jansson.
Having already made significant advances in other graphene/metal composites and coated powders for Additive Manufacturing, Graphmatech is now actively scaling up this technology due to the potential for graphene in enhancing the processability of powders and the properties of AM parts.
Dr Taher concluded, “This 3D printable hybrid material has the potential to add value in a range of sectors such as e-mobility, electronics and defence.”