Research for magnetocaloric effect of Gd_1–xDy_x alloy

Abstract

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 (∆T ) 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 ∆T 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 ∆T 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.

Advanced materials for magnetic cooling: Fundamentals and practical aspects

“…On the other hand, their localized magnetism allows the use of simplified theoretical models, namely the mean field theory to predict their performance in functional magnetic cooling machines. Their magnetic and magnetocaloric properties have been extensively studied from both practical and fundamental points of view 19,52,[98][99][100][101][102][103][104][105][106][107][108][109][110][111] .…”

“…Following, Hou et al100 have investigated the adiabatic temperature change of Gd1-xDyx (x = 0 to 40 %) using commercial Gd and Dy with relatively low purity (up 99.8 %). When increasing the Dy content from 0 to 40 %, the Curie temperature was reduced from 288 to 245.5 K, while for a magnetic field of 1.2 T, the ΔTad at TC increases from 1.6 to 3.1 K, respectively.…”