Effect of microstructure and texture on the magnetic and magnetocaloric properties of the melt-spun rare earth intermetallic compound DyNi

Abstract

Magnetization measurements have been carried out on the melt-spun ribbon sample of the rare earth intermetallic compound DyNi (Orthorhombic, FeB-type, Space group Pnma) and its magnetic and magnetocaloric properties are compared with those of the arc-melted analog. The arc-melted DyNi orders ferromagnetically at around 61 K (T-C) whereas the melt-spun DyNi orders ferromagnetically at about 47 K. The maximum isothermal magnetic entropy change, Delta S-III(max), near T-C of the arc-melted and the melt spun DyNi is found to be -32.7 J/kg K and -22.4 J/kg K, respectively, for a field change of 140 kOe. For low magnetic field changes of similar to 20 kOe, the relative cooling power (RCP) is similar to 660 J/kg for the arc melted DyNi and similar to 460 J/kg for the melt-spun ribbon. The reduction in T-C and magnetocaloric effect may be attributed to the microstructure-induced anisotropy developed during the melt-spinning process. (C) 2016 Elsevier B.V. All rights reserved