SKM 2023 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

MA: Fachverband Magnetismus

MA 28: Bulk Materials: Soft and Hard Permanent Magnets

MA 28.2: Vortrag

Mittwoch, 29. März 2023, 09:45–10:00, POT 6

Magnetic properties of rare-earth-lean ThMn₁₂-type (Nd,X)Fe₁₁Ti (X: Y and Ce) compounds: A DFT study — •Stephan Erdmann, Thorsten Klüner, and Halil Ibrahim Sözen — Institute of Chemistry, Carl-von-Ossietzky University of Oldenburg, D-26129 Oldenburg, Germany

Due to the resource criticality of rare-earths (RE), an alternative to the well-known Nd₂Fe₁₄B magnets with a lower amount of critical elements is required. In this work, we performed density functional theory (DFT) calculations to investigate the influence of partial Nd substitution with more abundant elements (X: Y and Ce) in ThMn₁₂-type (Nd,X)Fe₁₁Ti compounds. In order to have a systematic understanding, the intrinsic magnetic properties such as saturation magnetization M_S, Curie temperature T_C and magnetocrystalline anisotropy energy, are screened starting from binaries RFe₁₂ (R: Y, Ce and Nd). Ti is considered for the thermodynamic stabilization and different concentrations of Ti are taken into account for ternaries RFe_12−yTi_y, and quaternaries (Nd,X)Fe_12−yTi_y (0.5≤y≤1). In addition, the effect of nitrogenation is examined for each considered compound. In case of (Nd,Y)Fe₁₁Ti, |BH|_max is found to be 384 kJ/m³ and T_C is calculated to be 595 K. Similarly, |BH|_max and T_C are calculated to be 365 kJ/m³ and 593 K for (Nd,Ce)Fe₁₁Ti magnet, respectively. Both 50 % Nd-lean magnets exhibit higher |BH|_max compared to Sm₂Co₁₇ and T_C than Nd₂Fe₁₄B. For both cases, our theoretical magnetic hardness factor κ is calculated to be 1.20, which qualifies them as good candidates for RE-lean permanent magnets.