The Potential of Rapid Solidification during PBF-LB/M of CuCrZr and CuCrNbZr Alloys to Increasing the Age Hardenability and Fatigue Resistance

• Applicants: Professorin Dr.-Ing. Katrin Jahns; Professor Dr.-Ing. Ulrich Krupp
• Subject Area: Materials in Sintering Processes and Generative Manufacturing Processes ; Mechanical Properties of Metallic Materials and their Microstructural Origins
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 559203771

Powder bed-based processes in additive manufacturing have made significant progress with respect to process parameter adaption, dedicated materials design and product quality. Intense research has been devoted to highly reflective metals, such as precipitation-strengthened CuCrZr or CuCrNb alloys. Their application as welding electrodes, rocket engines or heat exchangers with complex geometries of cooling channels requires high electrical and thermal conductivity combined with sufficient mechanical strength. The proposed research aims at an ICME-guided (integrated computational materials engineering) design of such alloys within an extended composition range. The very high cooling rates during metal powder atomization and subsequent laser-based powder bed fusion (PBF-LB/M) will allow for precipitation strengthening strategies beyond the conventional solutionizing and ageing treatment, i.e., hyper-eutectic solidification can be used to obtain primary nano-sized precipitates. By means of an iterative alloy design supported by high-resolution electron microscopy and mechanical testing, fatigue and creep resistant microstructures will be identified. The adjustment of the chemical composition will show the limits of age hardening in combination with the pre-existing hyper-eutectic nanoprecipitates in CrCrZr and CuCrNb alloys and provide new insights to extend the ICME process simulation routine for additive manufacturing.

• DFG Programme: Research Grants
• Co-Investigator: Dr.-Ing. Marion Cornelia Kreins