Thermal stability, magnetic and magnetocaloric properties of Gd55Co35M10 (M = Si, Zr and Nb) melt-spun ribbons

Abstract

The thermal stability, magnetic and magnetocaloric properties of Gd55Co35M10 (M = Si, Zr and Nb) melts-pun ribbons were studied. The relatively high reduced glass transition temperature (Tx1/Tm > 0.60) and low melting point (Tm) resulted in excellent glass forming ability (GFA). The Curie temperatures (TC) of melt-spun amorphous ribbons Gd55Co35M10 for M = Si, Zr and Nb were 166, 148 and 173 K, respectively. For a magnetic field change of 2 T, the values of maximum magnetic entropy change (−ΔSM)max for Gd55Co35Si10, Gd55Co35Zr10 and Gd55Co35Nb10 were found to be 2.86, 4.28 and 4.05 J kg−1K−1, while the refrigeration capacity (RC) values were 154, 274 and 174 J kg–1, respectively. The RCFWHM values of amorphous alloys Gd55Co35M10 (M = Si, Zr and Nb) are comparable to or larger than that of LaFe11.6Si1.4 crystalline alloy. Large values of (−ΔSM)max and RC along with good thermal stability make Gd55Co35M10 (M = Si, Zr and Nb) amorphous alloys be potential materials for magnetic cooling operating in a wide temperature range from 150 to 175 K, e.g., as part of a gas liquefaction process.