Regensburg 2022 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

MM: Fachverband Metall- und Materialphysik

MM 18: Poster Session 2

MM 18.25: Poster

Tuesday, September 6, 2022, 17:30–20:00, P2

Magnetic Hardening of Nd-Fe-B Permanent Magnets — •Lukas Schäfer¹, Konstantin Skokov¹, Fernando Maccari¹, Iliya Radulov¹, David Koch², and Oliver Gutfleisch¹ — ¹Functional Materials, Institute of Material Science, Technical University of Darmstadt, 64287, Darmstadt, Germany — ²Strukturforschung, Institute of Material Science, Technical University of Darmstadt, 64287, Darmstadt, Germany

Nd-Fe-B alloys used for permanent magnets provide highest performance and energy density and are therefore used in numerous energy and high-tech applications. The superior intrinsic properties of the hard magnetic Nd₂Fe₁₄B phase are translated by a controlled production processes leading to a specific micro- and grain boundary structure and high coercivity. In this work, we take a different approach and show a novel magnetic hardening mechanism in such materials. This mechanism has the potential to be incorporated into existing manufacturing processes and to be adapted to novel production routes for Nd-Fe-B permanent magnets such as Additive Manufacturing. As an example, we demonstrate how the microstructural transformation from metastable Nd₂Fe₁₇B_x phase to the hard magnetic Nd₂Fe₁₄B phase by controlled annealing leads to a significant increase in coercivity from  250 kAm⁻¹ to  700 kAm⁻¹ in Nd₁₆Fe_{bal−x−y−z}Co_xMo_yCu_zB₇ alloys. This approach offers also a promising opportunity for the fabrication of nano composite magnets.