Magnetic properties and magnetocaloric effect in amorphous Co35Er65 ribbon

•Magnetic properties and magnetocaloric effect of the amorphous Co35Er65 ribbon are reported.•Analysis of the magnetic ordering transition using the Landau theory and Arrott׳s plots reveals occurrence of a FOMT in the amorphous Co35Er65 ribbon.•The value of (−ΔSmax) reaches a maximum value of 5.97 J/kg K at 5 T field.

Amorphous Co35Er65 ribbon was synthesized using melt spinning technique. Their magnetic properties and magnetocaloric effect (MCE) have been studied by the magnetization and isothermal magnetization of different temperature measurements. It is found that the sample obeys to the first-order magnetic transition (FOMT) from ferromagnetic (FM) to paramagnetic (PM) state at the Curie temperatures TC=10 K. Using the thermodynamic Maxwell׳s relation, magnetic entropy change (−ΔSM)(−ΔSM) is estimated and discussed in terms of MCE. The ribbon presents a large magnetocaloric effect at low temperature reaching 5.97 J/K kg under magnetic field of 0–5 T.