Rare earth-free magnetocaloric material Fe₈₂Hf₆Zr₇B₄Cu₁ for high-temperature applications

The magnetocaloric effect (MCE) has garnered much attention in recent years, especially for rare earth (RE)-free magnetic materials. The increasing focus on these materials arises from their prospective uses in cryogenic magnetic cooling and elevated temperature environments. The study conducts a systematic experimental examination of a novel magnetocaloric material, Fe₈₂Hf₆Zr₇B₄Cu₁ ribbons, primarily aimed at characterising their structural, magnetic, and magnetocaloric properties. X-ray diffraction (XRD) analysis confirmed the successful incorporation of hafnium in the Fe site of the Fe-Zr-B-Cu matrix. Furthermore, the magnetic properties of the ribbon were also investigated, yielding a Curie transition temperature of 678 K and a magnetic entropy change of 0.448 J kg^-1 K^-1 at 2.0 T. Notably, the relative cooling power and refrigeration capacity were determined to be 11.87 J kg^-1 and 14.0 J kg^-1, respectively, highlighting the potential of the material for high-temperature magnetocaloric applications. These findings collectively demonstrate that the novel Fe₈₂Hf₆Zr₇B₄Cu₁ ribbon exhibits promising magnetocaloric properties, rendering it a suitable candidate for further investigation and potential applications in high-temperature magnetocaloric devices.