Title :
Large magnetic entropy change in compound LaFe11.44Al 1.56 with two magnetic phase transitions
Author :
Hu, Feng-xia ; Shen, Bao-Gen ; Sun, Ji-Rong ; Pakhomov, A.B. ; Wong, C.Y. ; Zhang, X.X. ; Shao-ying Zhang ; Wang, Guang-jun ; Cheng, Zhao-hua
Author_Institution :
Inst. of Phys., Acad. Sinica, Beijing, China
fDate :
7/1/2001 12:00:00 AM
Abstract :
It is shown that Fe-based compound LaFe11.44Al1.56 with cubic NaZn13-type structure undergoes both a second order and a first order phase transitions. In small fields, it orders antiferromagnetically at TN=186 K, and ferromagnetism is established at T0≈127 K. At T>T0, field-induced metamagnetic transition between the two phases is observed in larger fields. The magnetic entropy change |ΔS|, estimated as a function of temperature from magnetization curves, has large values near the first-order transition. Metamagnetic transformation leads to an asymmetric broadening of the maximum with increasing field. This compound may be useful for magnetic refrigeration
Keywords :
aluminium alloys; ferromagnetic-antiferromagnetic transitions; iron alloys; lanthanum alloys; magnetocaloric effects; metamagnetism; 127 K; 186 K; LaFe11.44Al1.56; asymmetric broadening; ferromagnetism; field-induced metamagnetic transition; first-order transition; magnetic entropy change; magnetic phase transitions; magnetic refrigeration; magnetocaloric effect; Antiferromagnetic materials; Entropy; Magnetic materials; Materials science and technology; Physics; Powders; Refrigeration; Saturation magnetization; Sun; Temperature distribution;
Journal_Title :
Magnetics, IEEE Transactions on
