Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Additive manufacturing of copper-graphene composites by 3D-Extrusion
Submission Author:
Milene Follmann , RS , Brazil
Co-Authors:
Milene Follmann, Camila Gonçalves, Manuela Furlani da Silva Soares, Natalia Daudt
Presenter: Milene Follmann
doi://10.26678/ABCM.COBEM2023.COB2023-1525
Abstract
Porous copper components are widely used in energy-related applications due to their outstanding electrical and thermal properties; however, their high density can be a disadvantage for e-mobility applications. Graphene, due to its excellent strength, low density, and thermal physical properties, has great potential for use as reinforcement in different composites, it can improve the specific strength of copper matrix composites, enabling the construction of lighter components. Additive manufacturing (AM) is an attractive route for manufacturing copper components with a complex shape and tailored porosity for applications such as cooled vehicle skin and heat exchangers. Sinter-based technologies are more suitable for isotropic metal composites. Among AM technologies, extrusion-based 3D printing is often applied for printing ceramics pastes, but it can be a compelling alternative for producing small batches and prototypes of metal and composite components. Therefore, the goal of this project was to investigate the viability of the 3D extrusion of graphene-reinforced copper composites. For that, a binder solution of carboxymethylcellulose was prepared, and it was dissolved in water in a mass ratio of 99/1, respectively. The binder was mixed with pure electrolytic copper and nanopellets of graphene, used as starting materials. Initially, graphene was dispersed in the aqueous solution used as binder. Then, the copper powder was added to the mixture and homogenized. The graphene compositions were 0,5%, 1%, and 3% of the powder load. Samples were printed in a house-customized 3D extrusion printer. For preliminary tests, pastes with 5g were prepared and molded in cold pressing equipment at 60 MPa. After printing/compaction, green samples were thermal debonded and sintered. Sintering was performed from 930ºC to 980°C for 120 min in a vacuum furnace. Subsequent to sintering, the composites underwent through metallography preparation. The samples were characterized regarding their microstructure by optical, porosity by Archimedes density method, and mechanical properties by microhardness and compression tests. The results obtained so far suggested that 3D extrusion is a viable route for the production of graphene-copper composites and that graphene acts as a strengthening of copper, increasing the mechanical strength while decreasing ductility.
Keywords
3D extrusion, Nanocomposites, Additive Manufacture, Copper-graphene, Copper
