Effect of Co addition on the magneto-caloric effect of Fe-based metallic glasses

Magnetic refrigeration, based on the magnetocaloric effect (MCE), has already been applied in low temperature applications. There are, however, limitations in room temperature applications, and many researchers are now working on this issue. The refrigeration capacity (RC), which reflects the MCE, of amorphous materials has been proven to be generally larger than that of crystals. Among various amorphous magnetic materials, although the Fe-based materials have general MCEs, their advantages of high Curie temperature (TC) and low cost have attracted considerable attention and investigation. In order to enhance the MCE, the influence of Co addition on a Fe-based amorphous material was investigated in this study. Fe76-xCoxSi5Cr4Zr5B10(x=0, 2, 4, 6) ribbons were fabricated and their MCE was studied under a maximum field of 1193.7 kA/m. The results show that Fe74Co2Si5Cr4Zr5B10ribbon demonstrated good performance when both refrigeration capacity and Curie temperature are taken into consideration (Tc=295K, RC=56.1J/kg). Since the Curie temperature of this alloy is close to room temperature. It is envisaged that with further improvement of its RC, this material is promising for magnetic refrigeration at room temperature.