The production of soft magnetic materials (SMMs) via additive manufacturing (AM) routes is a field of continuously growing interest. Most of the common soft magnetic alloying systems such as Fe-Si, Fe-Ni and Fe-Co have already been researched to varying extent in AM processes. On the other hand, the binary Fe-Al system is often overlooked when it comes to SMMs, even though some of its alloys have interesting features such as a very low coercivity, high permeability and very high specific electrical resistivity [1]. However, similar as with high-silicon Fe-Si alloys (e.g., Fe-6.5Si), the production of sheets by conventional hot and cold rolling processes is challenging and rarely viable due to a low ductility of the magnetically interesting alloys (e.g., Fe-12Al or Fe-16Al). AM processes that produce near-net-shape parts, could be one solution to overcome this issue and enable the production of soft magnetic components from these alloys.

For an Fe-12Al alloy additively manufactured via laser powder bed fusion (L-PBF), we take a closer look at the microstructure and magnetic properties resulting from this process [2]. With heat-treated L-PBF samples a coercivity H_c of 11.3 A/m and a maximum permeability µ_max of 13.1 × 10³ could be reached so far. While the DC properties of materials produced in casting and rolling experiments were not yet fully reached, the AM material showed lower iron losses than the rolled material in ring samples with identical dimensions. The general differences, potentials, but also challenges that may arise during the AM of SMMs are highlighted as well.

[1] C. Heck Magnetic Materials and Their Applications, 1974, Butterworths, London
[2] T. Kunert, T. Kresse, F. Fohr, N. Volbers, G. Schneider, D. Goll Metals, 2024, 14, 117