LAUSR

Abstract In this paper, a profound study has been conducted on magnetocaloric effect in (1-x)La0.7Ca0.25Sr0.05MnO3/xLa0.7Ca0.2Sr0.1MnO3 composite system. The present research work reveals an especial agreement between the experimental results and the continuous curves investigated by the numerical calculations in a two phases composite system (1-x)La0.7Ca0.25Sr0.05MnO3/xLa0.7Ca0.2Sr0.1MnO3. This approach can be used to elaborate magnetic material with enhanced magnetocaloric properties. In addition, the ability to adjust the temperature transition near room temperature is revealed to be possible by the mixture of both individual phases La0.7Ca0.25Sr0.05MnO3 and La0.7Ca0.2Sr0.1MnO3. Our samples have been synthesized using the solid state reaction. Rietveld refinement of the X-ray diffraction patterns reveals the same orthorhombic structure with Pnma space group for both component manganites. Magnetization measurements versus temperature in a magnetic applied field of 0.05T show that all our samples exhibit a paramagnetic ferromagnetic transition with decreasing temperature. The Curie temperature TC is found to be 282 K and 308 K for La0.7Ca0.25Sr0.05MnO3 and La0.7Ca0.2Sr0.1MnO3, respectively. Moreover, the magnetic entropy change and the Relative Cooling Power (RCP) values were estimated for the biphasic system (1-x)La0.7Ca0.25Sr0.05MnO3/xLa0.7Ca0.2Sr0.1MnO3 with 0