Magnetocaloric effect in polycrystalline la based manganites modified with Sr

Abstract

All In this paper, we present magnetocaloric properties of the polycrystalline La0.7Ca0.25Sr0,05MnO 3 compound prepared by the ceramic method. X-ray diffraction indicated a single-phase compound with a perovskite structure. The value of magnetocaloric effect has been determined from the measurements of magnetization as a function of temperature and an external magnetic field. ΔS was found to reduce from 8 J/kgK to 4.5 J/kgK under ΔH = 2 T, and the same time, the Curie temperature increase from 250 to 279 K for x = 0 and 0.05 respectively. From the functional point of view, the materials to be used for magnetic refrigeration should be characterized by the greatest possible entropy change near room temperature. The results from this work showed that La 0.7Ca0.25Sr0.05MnO3 is interesting material and potential candidate for magnetic refrigerants.