Tuning the magnetic and magnetocaloric properties of a compound via mixing (1-x).La0.67Ca0.33MnO3+x.La0.67Sr0.33MnO3 (x=0, 0.25, 0.50, 0.75, 1): Composite materials or composite compounds?

This study aims to optimize the magnetic and magnetocaloric properties of composite materials (or compounds) produced by mixing different ratios of two manganite compounds having different structural, magnetic, and magnetocaloric properties. The parent compounds were prepared using the sol-gel production method and the ultrasonic bath mixing technique was involved to prepare desired composite materials. SEM analyses revealed that the parents and composite materials have the same surface morphologies except for their grain sizes. EDS analyses were performed to identify the possible/candidate phases in the composite materials. These candidate phases are involved in refining XRD data. The fact that the Curie temperatures (TC) of the composite materials were found to be much higher than those of the parent compounds was another proof that composite compounds were obtained instead of composite materials by using the ultrasonic bath mixing technique. Although the TC of the composite compounds was higher than those of the parent compounds, the maximum magnetic entropy values were found to vary between the maximum magnetic entropy valuesof the parent compounds.