Irreversible and reversible magnetic entropy change in a Dy-based bulk metallic glass

The magnetic entropy change of a Dy-based bulk metallic glass (BMG) was investigated in the temperature range of 2–94 K. The alloy shows spin glass like freezing process around 18.5 K. Above the spin freezing temperature, the magnetic entropy change is negative with a minimum about −8.3 J⋅kg−1K−1, demonstrating its good magnetocaloric effect (MCE) performance. Below the spin freezing temperature, irreversible positive magnetic entropy change is obtained with a maximum of 27.7 J⋅kg−1K−1 indicating large internal entropy production, which relates to the random magnetic anisotropy.