Magnetic properties and magnetocaloric effect in La0.7Nd0.3Fe13−xSix compounds

Abstract The structural, magnetic and magnetocaloric properties in the cubic NaZn 13 -type La 0.7 Nd 0.3 Fe 13− x Si x compounds with x =1.2, 1.4, 1.6 and 1.8 are reported. All of the investigated samples are ferromagnetically ordered. The Fe saturation moment at 5 K is independent of Si concentration, having a value of 2.05±0.09 μ B , which suggests a high degree of localization. The Curie temperatures increase almost linearly with the increase in silicon concentration. The large Δ S M values obtained for samples with low Si content are mainly due to the first-order character of the transition at T C . The field-induced transition above T C causes an asymmetric broadening of the Δ S M peak towards higher temperatures for higher applied fields. With increasing Si content, the first-order character of the transition at T C is diminished, leading to lower Δ S M values. The potential use of these materials in magnetic refrigeration is discussed.