Effect of preparation cooling rate on magnetocaloric effect of Fe80P13C7 amorphous alloy

In this work, the magnetocaloric effect (MCE) of Fe80P13C7 melt-spun amorphous ribbon and bulk glassy rod has been investigated and so the effect of the preparation cooling rate on the MCE of the present Fe-based amorphous alloy is studied. The value of peak of isothermal magnetic entropy change (vertical bar Delta S-M(peak)vertical bar) and refrigerant capacity (RC) for the Fe80P13C7 amorphous ribbon is larger than those of the glassy rod under varies applied field. Hence, we consider that the demagnetization field effect may have a significant influence on the MCE measurement results of the Fe80P13C7 glassy rod. After the demagnetization field correction, the values of vertical bar Delta S-M(peak)vertical bar and RCAREA for the Fe80P13C7 glassy rod are close or even superior to those of the amorphous ribbon. Further, it is indicated from the vertical bar Delta S-M(peak)vertical bar proportional to H-n relationship that the glassy rod has more homogeneous internal atomic structure compared with the amorphous ribbon. It has been proposed that more homogeneous structure could lead to greater magnetocaloric properties, and therefore we suggest that the intrinsic MCE performance of the Fe80P13C7 glassy rod prepared at a lower cooling rate should be better than that of the amorphous ribbon.