Effects of crystallization treatment on the structure and magnetic properties of Gd65Fe25Zn10 alloy ribbons for magnetic refrigeration

•Gd65Fe25Zn10 alloys were prepared by melt-spinning followed by crystallization annealing.•TC is close to room temperature for as-annealed Gd65Fe25Zn10 alloys.•RC for Gd65Fe25Zn10 as-annealed alloys is higher than that of Gd5Si2Ge2 alloy.•Large (−ΔSM)max and negligible losses make the studied alloys suitable for magnetic refrigerant.

The structure and magnetic properties of Gd65Fe25Zn10 alloy ribbons prepared by melt-spinning followed by crystallization annealing were investigated. In the as-spun ribbons, there is a small amount of α-Gd nanocrystalline existed in the amorphous matrix. After crystallization treatment, besides the pre-precipitated α-Gd phase, GdFe2 and GdZn crystalline phases precipitated in turn in the amorphous matrix. The Curie temperature (TC) of the fully amorphous matrix is ∼250 K. Owing to α-Gd nanocrystalline precipitated in the amorphous matrix, a second order magnetic transition occurs near 288 K for both the as-spun and the as-annealed Gd65Fe25Zn10 ribbons. For a field change of 2 T, the maximum magnetic entropy change (−ΔSM)max for the as-spun and as-annealed ribbons are 1.56-2.31 and 3.83-4.06 J/(kg·K), while the values of refrigeration capacity (RCFWHM) are 224.0-387.0 and 149.5-158.0 J/kg, respectively. The as-spun Gd65Fe25Zn10 ribbons display relatively low (−ΔSM)max but the largest RCFWHM value due to the wide (−ΔSM) versus T curve peak. With negligible thermal/magnetic hysteresis losses, relative large (‒ΔSM)max and its peak temperature near room temperature, the Gd65Fe25Zn10 alloy ribbons can be used as the potential magnetic refrigeration material working at room temperature.