Thermal, magnetic and magnetocaloric properties of FeErNbB metallic glasses with high glass-forming ability

Abstract The comprehensive characteristics of Fe71-xErxNb6B23 (x = 0, 1, 3, 5, 7 at.%) bulk metallic glasses (BMGs), including the thermal properties, glass-forming ability, magnetocaloric effect and mechanical properties were investigated. As a result, with increasing Er content up to 5 at.%, the supercooled liquid region increases to 90 K, and BMG with a critical diameter of 4 mm is fabricated by copper mold casting. The regulation of Curie temperature is achieved by controlling the amount of Er. The resulting glass alloy system exhibits Curie temperature of 340–550 K, magnetic entropy change of 0.74–1.41 J/kg K, and refrigerant capacity of 56–112 J/kg in external magnetic field of 1.5 T. Moreover, the Fe71-xErxNb6B23 BMGs exhibit high saturation magnetic flux density of 0.43–1.09 T, high fracture strength of 3.09–4.65 GPa and high Vickers hardness of 1030–1090 kg/mm2, respectively. Considering these good overall characteristics, this glass alloy system can be employed as magnetic-refrigerant materials in temperature range of 340–550 K.