article
Magnetocaloric properties of rapidly solidified Dy3Co alloy ribbons
Autor
Sánchez Llamazares, José Luis
Flores Zúñiga, Horacio
Álvarez Alonso, Pablo
Sánchez Valdés, Cesar Fidel
G. A. Lara Rodríguez
María Luisa Fernández-Gubieda Ruiz
Resumen
"The magnetic and magnetocaloric (MC) properties of melt-spun ribbons of the Dy3Co intermetallic compound were investigated. Samples were fabricated in an Ar environment using a homemade melt spinner system at a linear speed of the rotating copper wheel of 40 ms(-1). X-ray diffraction analysis shows that ribbons crystallize into a single-phase with the Fe3C-type orthorhombic crystal structure. The M(T) curve measured at 5mT reveals the occurrence of a transition at 32K from a first to a second antiferromagnetic (AFM) state and an AFM-to-paramagnetic transition at T-N = 43 K. Furthermore, a metamagnetic transition is observed below T-N, but the magnetization change Delta M is well below the one reported for bulk alloys. Below 12 K, large inverse MC effect and hysteresis losses are observed. This behavior is related to the metamagnetic transition. For a magnetic field change of 5 T (2 T) applied along the ribbon length, the produced ribbons show a peak value of the magnetic entropy change Delta S-M(peak) of -6.5 (-2.1) Jkg(-1) K-1 occurring close to TN with a full-width at half-maximum delta T-FWHM of 53 (37) K, and refrigerant capacity RC = 364 (83) Jkg(-1) (estimated from the product vertical bar Delta S-M(peak)vertical bar x delta T-FWHM)."