Functional magnetic materials, especially hard and soft magnets, are key components in many technologies [1]. Their increasing material demand requires an efficient fabrication and utilization of their raw materials. The production of permanent magnets has a long history and powder metallurgical routes are well established [2]. An interesting alternative production technique is additive manufacturing, which has the potential to produce complex geometries, print-in designs, locally tailored magnetic properties while retaining a resource-efficient use and fabrication. However, the production of fully dense permanent magnets with additive manufacturing is a challenging task since the composition and the microstructure must be carefully adjusted to obtain good magnetic properties [3], [4].

The production of large amount of powder of different compositions for LPBF experiments is economically not feasible. Therefore, a method for an efficient lab-scale qualification of hard magnetic materials for LPBF will be shown. This includes alloy design, characterization and the consolidation via LPBF of a small amount of powder. Strategies are presented to use a small amount of irregular shaped powder in the LPBF process to evaluate the suitability of a specific composition for the process. By varying the process window as broadly as possible, a statement on the subsequent adjustment of the targeted microstructure and the correlating functional properties are shown.

This work was supported by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), Project ID No. 405553726, TRR 270.We acknowledge the support by TU Darmstadt internal funds which were approved by the FiF (Forum für interdisziplinäre Forschung) committee.

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