Study of the magnetic and magnetocaloric properties of amorphous alloys formed by the ErxFe100−x series

• Published in: Journal of non-crystalline solids Vol. 649
• Main Authors: Freitas, V.L.O., Neto, P.P. Almeida, Costa, S.S., Alho, B.P., Ribeiro, P.O., de Sousa, V.S.R., von Ranke, P.J., Nóbrega, E.P.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2025
• Subjects: Amorphous alloys; Magnetism; Magnetocaloric effect; Magnetocaloric effect; Magnetism; Amorphous alloys
• ISSN: 0022-3093
• DOI: 10.1016/j.jnoncrysol.2024.123336

In this work, we investigate the magnetic and thermodynamic properties and the magnetocaloric effect of amorphous alloys formed from the series ErxFe100−x. To calculate the quantities on which the study is based, we use a Hamiltonian of interacting spins with two magnetic sublattices treated by the HPZ model, a modified Heisenberg Hamiltonian, in which each ionic spin is subject to a local anisotropy field of random orientation. The amorphous alloys studied present ferrimagnetic phase transitions, explained by the magnetic matrix composed of Er and Fe atoms. As a consequence, depending on the Fe doping, compensation temperatures, and inverse magnetocaloric effects are observed. Considerable values of refrigerant capacity in units of J kg−1 under the variation of 5 T of the applied magnetic field were found: 364, 380, 349, 291, and 237 for x=8.5,10,16.5,21.5 and 28, respectively. [Display omitted] •HPZ model for the magnetic and magnetocaloric description of amorphous alloys.•High magnetocaloric potentials in the room temperature range.•Microscopic mechanisms involved in the phase transitions of ferrimagnetic amorphous.