Magnetic phase transition and magnetocaloric effect in Dy 12Co7 compound

Abstract

Magnetic and magnetocaloric properties of Dy12Co7 compound have been investigated by magnetization measurements. Its magnetization does not reach saturation even for 7 T at 2 K due to the crystalline field effect. Dy12Co7 undergoes a ferromagnetic-paramagnetic phase transition around Curie temperature TC = 64 K. The thermomagnetic irreversibility between the zero-field-cooling and field-cooling curves is detected below TC in low magnetic field, and it is attributed to the narrow domain wall pinning effect. Large magnetic entropy change of 10.0 J kg-1 K-1 and refrigerant capacity of 299 J kg-1 for a magnetic field change of 0-5 T are found around T C, resulting from the large change of magnetization during the magnetic phase transition. The nature of second-order phase transition for Dy12Co7 induces the complete reversibility of magnetic entropy change around TC, which is very favourable for the application of magnetic refrigeration. © 2013 AIP Publishing LLC.