High performance Nd-Fe-B permanent magnets are key components for efficient electro mobility; they are as important as Li-ion batteries. Every battery needs a magnet, the higher the remanent magnetization, the higher the torque, the less magnet is needed and driving range can be extended [1].

95% of electric vehicles utilize rare earth magnet based drive motors, the quantities required global will grow from 5,000 t in 2019 to about 40,000 - 70,000 t/a in 2030 [1,2]. Alloy and microstructure design strategies for magnets performing well at operating temperatures of 120-180°C will be shortly explained; on a second level, mitigation strategies to address the criticality of the rare earth elements will be elucidated. This includes: (1) Diversification of primary mining and making it sustainable, (2) Material Science advances to reduce the utilization of critical materials, (3) Recycling to use the urban mine (technosphere) and (4) Substitution of strategic metals by (more) earth abundant elements [3].

Despite considerable progress in the modelling, characterization and synthesis of magnetic materials, hysteresis is a long-studied phenomenon that is still far from being completely understood. Discrepancies between intrinsic and extrinsic magnetic properties remain an open challenge and magnets do not operate yet at their physical limits. This is one of the topics of the DFG sponsored Cooperate Research Center HoMMage [4].

[1] O. Gutfleisch, et al., Magnetic materials and devices for the 21st century: stronger, lighter, and more energy efficient. Adv. Mater. 23 (2011) 82.

[2] Rare Earth Magnets and Motors: A European Call for Action. A report by the Rare Earth Magnets and Motors Cluster of the European Raw Materials Alliance. Berlin 2021, R. Gauss, ..O. Gutfleisch,  et al.

[3] K.P. Skokov, O. Gutfleisch, Heavy rare earth free, free rare earth and rare earth free magnets - vision and reality, Scripta Materialia 154 (2018) 289-294.

[4] https://www.tu-darmstadt.de/sfb270