Thermal stability and magnetocaloric properties of GdDyAlCo bulk metallic glasses

Magnetocaloric Effect in Uncoated Gd55Al20Co25 Amorphous Wires

“…Moreover, the series of refrigerants with first-order magnetic transition (FOMT) such as La(Fe,Si) [3] , Gd(GeSi) [4] and MnFePAs [5] alloys and with second-order magnetic transition (SOMT) e.g. pure Gd [6] , Gd-based [7] and Dy-based [8] alloys are developed for MR which applied in liquid nitrogen or room temperatures.…”

“…Gd is a unique member of the lanthanide series with large magnetic moment and its ground-state electronic configuration is 4f [7] (5d6s) [3][4][5][6][7][8][9] . In contrast to other rare earth metals, Gd has no orbital momentum, leading to a relatively small magnetocrystalline anisotropy and a wide composition range which is possible by alloying predominantly magnetic 3d transition elements 10 .…”

Gd–Dy–Al–Co bulk metallic glasses with large magnetic entropy change and refrigeration capacity

“…We have reported our findings of the excellent magnetic entropy changes of 15.78 J kg −1 K −1 , 13.86 J kg −1 K −1 and 9.64 J kg −1 K −1 in Gd 40 Dy 16 Al 24 Co 20 , Gd 36 Dy 20 Al 24 Co 20 , and Gd 34 Dy 22 Al 24 Co 20 , respectively [16]. In this work, we further investigate the MCE of Gd-Dy-Al-Co bulk metallic glasses by changing the content of Dy in these glassy alloys.…”

“…The glass transition temperature, T g , and first crystallization temperature, T x , are 589 K, 634 K for Gd 56 Al 24 Co 20 , and 599 K, 658 K for Gd 42 Dy 14 Al 24 Co 20 , respectively, resulting in the supercooled liquid region, T x (=T x − T g ), of 45 K and 59 K. Obviously, the addition of Dy not only increases the thermal stability via T g and T x but also the T x . The decrease of Al in Gd 56 Al 24 Co 20 by 1% as compared with Gd 55 Al 25 Co 20 [11,[16][17][18], does not change T g obviously, but increases the T x by 20 K. 2 shows the temperature dependence of the magnetization (M-T curve) of specimen in field cooling (FC) mode in a field of 200 Oe at the temperature range of 305-2 K. The Curie temperature (T C ), which is defined by the minimum in the temperature dependence of the first order derivative of the magnetization (dM/dT, where M is the magnetization and T is the temperature), have been determined from the M-T curve (as shown in the inset of Fig. 2).…”

“…4 shows the variation of S M and magnetic transition temperatures with the content of Dy in Gd-(Dy)-Al-Co bulk metallic glasses. Some data are collected from other references [14,16]. As mentioned before, the amount of Dy contributes to the decline of the transition temperature of this system.…”