Direct magnetocaloric measurements of Fe-B-Cr-X (X = La, Ce) amorphous ribbons.

A procedure has been developed to directly measure the adiabatic temperature change of amorphous melt-spun Fe-based ribbons displaying attractive room temperature magnetocaloric properties. Polycrystalline Gd ribbons are used as a reference material to compensate for the contribution of the sample holder to the experimental values. Fe78B12Cr8Ce2 and Fe75B12Cr8Ce5 melt-spun ribbons exhibited a peak adiabatic temperature change (ΔTadpk) ∼ 58% larger than Co82.9Si5.9Fe4.5Cr4B2.7 amorphous ribbons. The ΔTadpk in Fe78B12Cr8Ce2, Fe75B12Cr8Ce5, and Fe79B12Cr8La1 ribbons displayed ∼ 18-33% enhanced ΔTadpk compared to a GdAl2 alloy. [ABSTRACT FROM AUTHOR]