Magnetocaloric properties of bulk Fe2AlB2 synthesized by reactive hot isostatic pressing

This study presents a new single-step synthesis of Fe2AlB2 at 1150°C for 4 hours using hot isostatic pressing (HIPing). X-ray diffraction confirmed the material as single-phase, while metallographic etching revealed predominant equiaxial Fe2AlB2 grains (~25 μm) and minor unreacted boron particles and Al-rich zones at grain boundaries. Magnetocaloric investigations demonstrated an impressive isothermal entropy change of 2.9 J/kg.K at 2 T and 6.8 J/kg.K at 5 T, with corresponding adiabatic temperature changes of 1.1 K and 2.8 K at 2 and 5 T, respectively. The HIPed Fe2AlB2 performance matches that of studies without post-treatments or doping. Fe2AlB2, composed of light and earth-abundant elements, can be synthesized in a single step using HIPing, making it an attractive option for magnetic refrigeration with improved energy efficiency and simplified manufacturing.