Magnetization behavior and magnetocaloric effect in bulk amorphous Fe60Co5Zr8Mo5W2B20 alloy

Abstract Microstructure by X-ray diffraction and Mossbauer spectroscopy, and isothermal magnetic entropy changes in the bulk amorphous Fe 60 Co 5 Zr 8 Mo 5 W 2 B 20 alloy in the as-quenched state and after annealing at 720 K for 15 min are studied. The as-cast and heat treated alloy is paramagnetic at room temperature. The quadrupole splitting distribution is unimodal after annealing indicating the more homogenous structure in comparison with that for the as-cast alloy. Curie temperature slightly increases after annealing from 265±2 K in the as-quenched state to 272±2 K and the alloy exhibits the second order magnetic phase transition. The maximum of isothermal magnetic entropy changes appears at the Curie points and is equal to 0.30 and 0.42 J/(kg·K) for the alloy in the as-quenched state and after annealing, respectively. In the paramagnetic region the material behaves as a Curie–Weiss paramagnet.