Influence of Al substitution on magnetocaloric effect of Pr2Fe17−xAlx

The structural and magnetic properties of the Pr2Fe17−xAlx (x = 0, 0.25, 0.5, 0.75, 1) compounds synthesized by arc-melting were investigated. The X-ray diffraction (XRD) coupled with the Rietveld analysis indicate that all samples are single phase with the rhombohedral Th2Zn17 type structure. Moreover, it reveals a 6c preferential occupation for the substituting element Al atoms in R3¯m. The unit cell volume increases slightly with increasing aluminum content while the c/a ratio remains constant. The study of magnetic properties reveals that Curie temperature increases with the Al content. The magnetic entropy change ΔSM was estimated from isothermal magnetization curves and it decreases with the increase of Al content from 5.5 J kg−1 K−1 (x = 0) to 4.2 J kg−1 K−1 (x = 1) at μ0H=5T. The saturation magnetization Ms, the magnetocaloric effect (MCE) of the compounds and the relative cooling power (RCP) were determined by measuring their magnetic properties.