Multimetal material jetting with copper materials

• Applicant: Professor Dr.-Ing. Wolfram Volk
• Subject Area: Primary Shaping and Reshaping Technology, Additive Manufacturing
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 524939160

Pure copper has excellent thermal and electrical conductivity, but comparatively low mechanical strength. In comparison, copper-tin bronzes have higher strengths but lower thermal and electrical conductivity. In order to combine the advantages of both materials in one component and thus achieve special properties at the local load point, the production of material composites is necessary. If components with high geometric complexity and/or small quantities are required, this is usually only possible with additive manufacturing processes. Due to the high thermal conductivity and the low absorption coefficient of the material copper compared to the currently widespread red laser sources, the processing of copper with the currently established additive manufacturing processes such as laser beam melting is difficult. The material jetting process, which does not require a laser source and powdered semi-finished products, therefore offers considerable potential for the cost-effective production of multi-material components made of copper materials. By building up a component layer from individual droplets, the material change can in principle be carried out within a droplet. For example, filigree cooling structures can be realised in a component in order to specifically improve thermal management in high-performance components. In addition, compared to powder bed-based processes, there is no mixture of the different starting powders after the component production that has to be separated or disposed. Within the scope of the research project, proof of the principle manufacturability of multi-material components in the material jetting process with controllable quality of the material compound is to be provided. To this end, suitable print head systems will be developed at the beginning (WP1) in order to be able to produce multi-material components with discrete and graded material interfaces. With the developed systems, the drop generation process will then be investigated (WP2) in order to identify a suitable parameter set for stable droplet generation. In the following work package (WP3), multi-material components are produced from Cu-ETP and CuSn8 with varied parameters. Different arrangements of the two materials in relation to each other are taken into account, which may also occur in possible later applications. The manufactured components are then characterised (WP4). Special focus is placed on the characterisation of the connection zone between the different materials. In addition, a virtual representation of the MJT process is carried out by means of a multi-scale simulation (WP5) in order to gain knowledge about the temporally and spatially resolved temperatures in the component during the manufacturing process.

• DFG Programme: Research Grants
• Co-Investigator: Professor Dr.-Ing. Philipp Lechner