Two award winners in Functional Materials

The Advisory Board of the TU Darmstadt Energy Center e.V. has announced the winners of this year's Darmstadt Energy Prize. The best master theses and dissertations from energy research at TU Darmstadt were awarded. The award ceremony took place on March 23 as a virtual event.

New publication

Pinning-type magnets with high coercivity at high temperatures, especially Sm2Co17-type magnets, are at the core of thriving clean-energy technologies. Despite intensive efforts to optimize the intragranular microstructure, the coercivity currently only reaches 20–30% of the theoretical limits.

New publication

Ce-based intermetallics are interesting for hard magnetic compounds; utilizing rare-earth balanced material systems could help to mitigate shortcomings in the supply of rare earth resources due to the monopolistic market and growing demands.

In the Newsletter of EIT Raw Materials the project UPGRADE – Optimised process for new permanent magnet grades with low content of heavy rare earth, of which functional materials is also part of, is presented.

We congratulate our colleague Andreas Taubel to his very successfull PhD defense.

3D-printed magnets help create more efficient electric motors

As part of the EIT-Raw Materials funded 3DREMAG consortium the group Functional Materials (FM) promotes with its profound experience in the field of permanent magnetic materials the development of a Nd-Fe-B powder designed for a resource efficient additive manufacturing (AM) process. The challenge is to transfer the knowledge from established magnet production routes to AM, since the quality of the printed magnets depends on the initial powder, which requires both spherical shape and chemical composition to result in a fully dense permanent magnetic part with a nanostructure effective for magnetic hardening. Tasks of FM in 3DREMAG are the alloy design, the magnetic and microstructural characterization of the powder and parts as well as the education of students and co-workers in the consortium.

New publication

The increasing demand for artificial cold and the ever-growing importance of climate protection call for new energy-efficient and environmentally-friendly alternatives to the conventionally used vapor-compression technology. The most promising candidate is solid-state caloric cooling which is based on the thermal response of a material to an external stimulus such as magnetic field, electric field, uniaxial stress or hydrostatic pressure. In our joint work with researchers from Helmholtz-Zentrum Dresden-Rossendorf and Universidad de Barcelona we demonstrate that the combination of more than one external stimulus can largely outperform the single caloric response.

New publication

New publication

L. Pfeuffer, T. Gottschall, T. Faske, A. Taubel, F. Scheibel, A. Y. Karpenkov, S. Ener, K. P. Skokov and O. Gutfleisch Phys. Rev. Materials 4, 111401 (2020) https://doi.org/10.1103/PhysRevMaterials.4.111401

Tailoring magnetocaloric effect in all-d-metal Ni-Co-Mn-Ti Heusler alloys: a combined experimental and theoretical study

Novel Ni-Co-Mn-Ti all-d-metal Heusler alloys are exciting due to large multicaloric effects combined with enhanced mechanical properties. We show that an optimized heat treatment leads to very sharp phase transitions in bulk alloys with large isothermal entropy changes.