Strong permanent magnets based on rare earth elements are a requirement for future mobility and sustainable electricity generation. Wind turbines, which are expected to contribute more electricity with every passing year, and electric cars, which need to be both energy and resource-efficient, both rely on strong permanent magnets. A permanent magnet with an increased efficiency of 2 % can increase the range of a car by 20 km. Changing the temperature of a material by the application of an external magnetic field is the principle behind the magnetocaloric effect. This principle will enable us to operate refrigerators and air-conditioning devices quietly, with low energy consumption and without the use of traditional refrigerants, themselves strong greenhouse gases.
Requirements: Affordable, environmentally friendly and efficient
All of these technologies rely on efficient magnet materials as their key components. However, they often contain raw materials which are rare, toxic and expensive. The researchers of the new CRC 270 HoMMage, which stands for “Hysteresis Design of Magnetic Materials for Efficient Energy Conversion”, are headed by Professor Oliver Gutfleisch from TU Darmstadt and are searching for new materials which operate close to their physical limits and are made from earth abundant materials.
Together with their colleagues from Max-Planck-Institut für Eisenforschung (MPIE) and Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons at Jülich Research Centre, the scientists of both universities will develop new processing methods for innovative magnet materials. Material scientists, physicists, chemists and process engineers will work on magnetic materials by manipulating individual atoms but also by deforming massive samples. By linking the experimental and theoretical groups together in one centre they will be able to continuously cross-link their developments. Artificial intelligence, which accelerates materials discovery and the rapid identification of the most promising material combinations, will also be employed in HoMMage.
Understanding the smallest detail
“We want to gain a detailed understanding of what is happening within the material, or in other words, identify the DNA of the magnet”, explains CRC 270-speaker Oliver Gutfleisch, Professor of Functional Materials at TU Darmstadt. ” That includes how the structural, magnetic and electronic interactions look like at the atomic level up all the way to the 2 kg of magnets that are placed in the electric motor of a car.” This knowledge will enable adjusting the local and global properties of a magnetic material by additive manufacturing and severe plastic deformation methods. “To achieve this goal, we have developed new ideas for processing techniques on all length scales, so that we can place the precious elements in the bulk magnet only where really needed”, co-speaker Professor Michael Farle from UDE adds.
The activities of CRC 270 HoMMage are embedded in two profile areas “From Material to Product Innovation” and “Future Energy Systems” of TU Darmstadt as well as in the key research area “Nanoscience” of UDE.
Sonja Laubach/Birte Vierjahn