Abstract:Investigation on magnetocaloric effects, magnetic entropy, Curie temperature and specific heat of nanocomposite binary gadolinium alloys Gd-Tb, Gd-Zn and Gd-Y has been fulfilled with an applied magnetic intensity 1 T and in a temperature range 233~313K. Compared with the same bulk alloys, the asprepared nanocomposite alloys show increasing specific heat and decreasing Curie temperature. The nanocomposite alloy Gd-Y even reveals the distinctive enhancement of both magnetocaloric effects and magnetic entropy over that of the same bulk alloy, which is of importance on developing new substance materials for practical magnetic refrigeration. A discussion concerning enhanced magnetic entropy in nanometer superparamagnetic system is presented in detail.

Key words: nanocomposites　magnetic refrigeration　rare earth