Magnetic properties and magneto-caloric effect in pseudo-binary intermetallic (Pr,Dy)2Fe17

Magnetic cooling could be a potential different energy solution substituting conventional vapour compression refrigeration in the future. For the largest cooling effects of most potential refrigerants, we need to exploit the different degrees of freedom such as magnetism and crystal structure. In order to realize this type of study, we have synthesized five pseudo-binary of bulk and nanostructured Pr-2 xDy(x)Fe(17) intermetallics alloys, where praseodymium has been partially substituted by dysprosium for obtaining the maximum magneto-caloric response of the alloys around room temperature. The influence of Dy substitution for Pr on the structure and magnetic properties of Pr-2 xDyxFe17 compounds with x = 0-0.5 was investigated. The analysis of the X-ray powder diffraction patterns show that the samples crystallize in the rhombohedral Th2Zn17-type crystal structure (space group R (3) over barm). The unit cell volume decreases slightly with increasing dysprosium content while the c/a ratio remains nearly constant. The Curie temperature increases from 285 K at x = 0 to 314 K at x = 0.5. This variation is due to electronic effect. The temperature dependence of the magnetization, the magnetic entropy change Delta S-M, as well as the relative cooling power around the second-order magnetic transition and the Arrott plots for the alloys are reported. (C) 2013 Elsevier B.V. All rights reserved.