Permanent Magnets

However, there are major problems with present-day permanent magnets. Currently, the most powerful permanent magnets contain significant amounts of rare-earth materials, specifically Neodymium and Dysprosium. These are mined in China, with great environmental consequences and also global supply challenges.
Transitioning to rare-earth-free magnets is a key challenge in the green transition. Such rare-earth-free magnets do exist, such as the well-studied ferrite magnets, but these currently have weak properties and are not suitable for use in many technologies.

At DTU Energy, we study magnetism on two length scales.
On the microscale we study novel rare-earth-free permanent magnets through the use of advanced micromagnetic models that we realize in-house. We use these to determine ideal material properties and microstructure to produce a powerful permanent magnet. However, we also study how to combine existing magnetic materials on the microscale to enhance their properties.

On the macroscale we research novel design optimization strategies, relying on both in-house methods and topology optimization, to design magnetic structures for applications that require a specific magnetic field using the least amount of permanent magnets.
We also study various energy technologies such as thermomagnetic energy harvesting, magnets for magnetic refrigeration, vibrational energy harvesting using permanent magnets and magnetic levitation, realizing experimental prototypes for each of these technologies.