中国物理B ›› 2006, Vol. 15 ›› Issue (4): 845-849.doi: 10.1088/1009-1963/15/4/031
张宏伟1, 董巧燕1, 张立刚2, 汪汝武2, 陈静3
Chen Jing (陈静)ab, Zhang Hong-Wei (张宏伟)b, Zhang Li-Gang (张立刚)a, Dong Qiao-Yan (董巧燕)b, Wang Ru-Wu (汪汝武)a
摘要: The unit cell volume and phase transition temperature of LaFe11.4Al1.6Cx compounds have been studied. The magnetic entropy change, refrigerant capacity and the type of magnetic phase transition are investigated in detail for LaFe11.4Al1.6Cx with x=0.1. All the LaFe11.4Al1.6Cx (x=0--0.8) compounds have the cubic NaZn13-type structure. The addition of carbon atoms brings about a considerable increase in the lattice parameter. The bulk expansion results in the change of phase transition temperature ($T_{\rm c})$. Tc increases from 187\,K to 269\,K with x varying from 0.1 to 0.8. Meanwhile an increase in the lattice parameter can also cause a change of the magnetic ground state from antiferromagnetic to ferromagnetic. Large magnetic entropy change \vert \Delta S\vert is found over a large temperature range around Tc and the refrigerant capacity is about 322J/kg for LaFe11.4Al1.6C0.1. The magnetic phase transition belongs in weakly first-order one for x=0.1.
中图分类号: (Magnetic phase boundaries (including classical and quantum magnetic transitions, metamagnetism, etc.))