Research for magnetocaloric effect of Gd 1–x Dy x alloy

The magnetocaloric effect (MEC) in Gd 1–x Dy x (x = 0.13, 0.20, 0.27, 0.34, 0.40) alloys is investigated using commercial elements with purity of up to 99.80% for Gd and Dy. These alloys are prepared by arc melting in stoichiometric proportions on a water‐cooled copper crucible under high pure argon atmosphere. As a result, when x was changed from 0 to 40at%, the adiabatic temperature change (ΔT) increases from 1.6 K to 3.1 K, the Curie temperature decreased from 288 K to 245.5 K. Gy 73 Dy 27 exhibits the largest ΔT max value of 3.1 K at the T C value of 260 K among the alloys investigated up to 1.2 T (tesla) applied field, it is almost same as the ΔT of high pure unitary Gd (99.99%) and is clearly superior to commercial unitary Gd (99.80%). The T C of Gy 73 Dy 27 alloy is minor to high pure unitary Gd (99.99%) and commercially unitary Gd (99.80%). But this alloy prepared by commercial elements with low cost has better MEC to be a promising candidate for magnetic working substances for room temperature magnetic refrigeration. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)