Magnetocaloric effect in Sm-Co2-xFex alloys
SmCo2 and SmFe2 magnetic cubic Laves phases have Curie temperatures of 220 and 669 K, respectively. Aiming to increase the Curie temperature of SmCo2 for potential room temperature magnetic refrigeration Co was partially replaced by Fe. The fundamental magnetic entropy change of the SmCo2 compound,...
| Autores: | , , |
|---|---|
| Formato: | artículo |
| Estado: | Versión enviada para evaluación y publicación |
| Fecha de publicación: | 2012 |
| País: | México |
| Recursos: | Centro de Investigación en Materiales Avanzados |
| Repositorio: | Fuente de Objetos Científicos Open Access del CIMAV |
| Idioma: | inglés |
| OAI Identifier: | oai:cimav.repositorioinstitucional.mx:1004/1048 |
| Acesso em linha: | http://cimav.repositorioinstitucional.mx/jspui/handle/1004/1048 |
| Access Level: | acceso abierto |
| Palavra-chave: | info:eu-repo/classification/SmCo2/Magnetocaloric effect info:eu-repo/classification/cti/1 info:eu-repo/classification/cti/22 info:eu-repo/classification/cti/2299 info:eu-repo/classification/cti/229999 |
| Resumo: | SmCo2 and SmFe2 magnetic cubic Laves phases have Curie temperatures of 220 and 669 K, respectively. Aiming to increase the Curie temperature of SmCo2 for potential room temperature magnetic refrigeration Co was partially replaced by Fe. The fundamental magnetic entropy change of the SmCo2 compound, ΔSM = 3.61 J/kg.K, for an applied magnetic field of μoH = 1.5 T was observed at TSR=175 K, where a spin reorientation transition occurs; furthermore a refrigerant capacity of 37 J/kg was calculated. Interestingly the addition of Fe practically suppressed the spin reorientation transition, shifting the magnetic entropy change maximum to the Curie temperature in the SmCo1.8Fe0.2 sample. The magnetic entropy change maximum at Curie temperature TC=300 K and the refrigerant capacity for the doped compound decreased to ΔSM=0.20 J/kg.K and 13.5 J/kg, respectively, for an applied magnetic field of μoH=1.5 T. After an homogenization heat treatment at 773K during 50 h, the SmCo1.8Fe0.2 compound showed an increase of the maximum magnetic entropy change, ΔSM=0.28 J/kg.K, and refrigerant capacity remains 13.5 J/kg, for an applied magnetic field of μoH=1.5T. |
|---|