Magnetocaloric effect and critical parameters of Fe90-xGdxZr10 rapidly quenched alloy ribbons

Abstract

e_90-xGd_xZr₁₀ (x = 1, 2 and 3) alloy ribbons with the thickness of about 30 μm have been prepared by using a melt-spinning technique. X-ray diffraction analysis has shown an amorphous structure of the alloy ribbons. Curie temperature, TC of the alloy ribbons have been considerably increased, from 252 K (for x = 1) to 326 K (for x = 3), by increasing the Gd concentration.The maximum magnetic entropy change,|∆S_m|_max, of the alloys is larger than 0,8 J∙kg^-1K^-1 with magnetic field change DH = 11kOe. A quite high refrigerant capacity (RC ~ 90 J∙kg^-1) at room temperature region has been obtained for the alloy ribbon with x = 2. Critical analyses around the ferromagnetic-paramagnetic phase transitions by using the Arrott-Noakes method have elucidated the magnetic orders in the alloys.