Graphene used to increase printability of copper for additive manufacturing
Researchers have used graphene to increase the printability of copper powder for additive manufacturing.
The hybrid material, developed in collaboration with Swedish firm Graphmatech, has the potential to add value in a range of sectors such as e-mobility, aerospace, electronics and defence.
Printing copper structures is sought after due to the material’s exceptional thermal and electrical properties, which enables it to be used for parts such as heat exchangers, electrical components and moulds.
However, copper has proven a challenge to process using lasers due to its high reflectivity.
At the infrared wavelengths commonly used in laser powder bed fusion, less than 10 per cent of the energy is absorbed by the material, resulting in printed parts with low density.
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While other approaches to printing copper involve the use of blue or green lasers, which exhibit higher absorption than infrared lasers, through using Graphmatech’s graphene technology, researchers from Uppsala University have instead modified the surface of copper powder to lower its reflectance by 67 per cent. The graphene survives the printing process to positively impact the density of the printed copper-graphene parts, significantly reducing their porosity.
‘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 Ulf Jansson, whose research group carried out the work.
Graphmatech is now actively scaling up this technology, having already made significant advances in other graphene-metal composites and coated powders for additive manufacturing with project partners, due to the potential for graphene in enhancing the processability of powders and the properties of printed parts.