Enhanced Curie temperature and cooling efficiency in melt-extracted Gd50(Co69.25Fe4.25Si13B13.5)50 microwires

Abstract

We report enhancements of both Curie temperature and magnetic refrigerant capacity in Gd 50 (Co 69.25 Fe 4.25 Si 13 B 13.5) 50 microwires, which were fabricated by the melt-extraction method. For a field change of 5 T, the maximum magnetic entropy change (-ΔS M max), the refrigerant capacity (RC) and relative cooling power (RCP) reached high values of 6.56 J•kg-1 •K-1 , 625 J•kg-1 and 826 J•kg-1 , respectively. While the RC is similar to those of our previously reported GdAlCo microwires, a much broader working temperature range of ~126 K and a higher Curie temperature of 170 K make the Gd 50 (Co 69.25 Fe 4.25 Si 13 B 13.5) 50 microwires more attractive for active magnetic refrigeration.

Observation of a Broadened Magnetocaloric Effect in Partially Crystallized Gd60Co40 Amorphous Alloy

“…In comparison with the table-like MCE in other alloys at analogous temperature ranges, such as Gd 55 Co 35 Mn 10 annealed at 600 K for 30 min (|∆S M | of 5.46 J•kg −1 •K −1 with a temperature range from 137 K to 180 K) [14] and fully crystallized Gd 55 Co 35 Ni 10 (620 K/30 min) ribbon (|∆S M | of 5.0 J•kg −1 •K −1 with a temperature range from 154 K to 214 K) [15], as listed in Table 1, the |∆S M | of the materials in this work are larger, but the temperature width of the plateau of |∆S M |-T is narrower. On another hand, when compared with single amorphous phase alloys, like Gd 75 (Fe 0.25 Co 0.75 ) 25 [24] and Gd 50 (Co 69.25 Fe 4.25 Si 13 B 13.5 ) 50 [25], the combined merits of larger or comparative |∆S M | and broader working temperature range can be observed in these Gd 60 Co 40 annealed samples. The MCE in a temperature range of 160-220 K can be used in the fields of space technology, medicine, biology, life sciences and more [14].…”

“…Gd-TM (TM = Co, Fe, Ni, and Mn) amorphous alloys with near-room temperature MCE have attracted more attention in recent years. Generally, the broadened |∆S M |-T profile can be observed in these materials, owing to the highly disordered structure of amorphous systems, which smears out the magnetic transition [1,11,15,[17][18][19][20][21][22][23][24][25][26]. In-situ crystallization treatment of the amorphous ribbons is also utilized to obtain multi-phase magnetic refrigerant, such as crystallized Gd 55 Co 35 Ni 10 ribbon containing Gd 4 (Co, Ni) 3 and Gd 12 (Co, Ni) 7 phases, and partially crystallized Gd 55 Co 35 Mn 10 with precipitation of the Gd 3 Co-type and Gd 12 Co 7 -type phases in the amorphous matrix, both of them possess broadened table-like MCE [14,15].…”

Outstanding Comprehensive Performance of La(Fe, Si)13Hy/In Composite with Durable Service Life for Magnetic Refrigeration

“…Pure Gd, as the benchmark magnetic refrigerant, is commonly used in the active magnetic regenerator prototypes . In particular, Gd metal could be produced into different shapes due to its good mechanical properties, such as thin plate, sphere, and microwire, and it has been demonstrated that microwire is more desirable for realizing a higher cooling performance . However, Gd metal also has its disadvantages such as relatively low magnetic entropy change (Δ S M ), limited availability, and expensive price that hinder its large‐scale commercialization.…”

Magnetocaloric effect and microstructure of amorphous/nanocrystalline HoErFe melt-extracted microwires

“…Although the technology has a wide application, many devices have relatively low Carnot efficiency (often less than 25%), and environmental concerns associated with leakage of the gaseous refrigerant. Increasingly, researchers are exploring alternative cooling technologies that may be more environmentally friendly and energy efficient that can be commercialized in the near future [1][2][3][4][5]. Magnetic refrigeration is a promising technology with potential advantages over conventional approaches, such as high energy efficiency, lack of a gaseous refrigerant, and environmental friendliness.…”