Effects of iron substitution on magnetic properties of SmCo6.8−xFexHf0.2 compounds

The effects of iron substitution on the crystal structure and magnetic properties of SrHCo6.8-xFexHf0.2 (x = 0.1, 0.3, 0.5, and 0.7) compounds were investigated by means of x-ray powder diffraction and magnetic measurements. The as-east SMCo6.8-xFexHf0.2 compounds crystallize in the TbCu7-type structure with the space group P6/mmm. The lattice parameters a and c increase with the Fe content. The SMCo6.8-xFexHf0.2 compounds exhibit ferromagnetic order with a strong room temperature uniaxial magnetocrystalline anisotropy. The Curie temperature and saturation magnetization increase with the Fe content. The magnetic anisotropy field of the compounds reaches a maximum value at x = 0.5. The anomalous concentration dependence of the anisotropy field is explained by considering the contribution of individual site anisotropy in combination with the preferential occupation of 3d ions on different sites.

[1]  Yongquan Guo,et al.  Effects of Cu on crystallographic and magnetic properties of Sm(Co,Cu)7 , 2003 .

[2]  G. Hadjipanayis,et al.  Structure and magnetic properties of RCo7−xMnx alloys (R=Sm, Gd; x=0.1–1.4) , 2002 .

[3]  Ralph Skomski,et al.  Sm–Co–Cu–Ti high-temperature permanent magnets , 2000 .

[4]  J. Liu,et al.  Structure and magnetic properties of SmCo7−xTix with TbCu7-type structure , 2000 .

[5]  D. Dimitrov,et al.  Abnormal temperature dependence of intrinsic coercivity in Sm(Co, Fe, Cu, Zr)z powder materials , 1998 .

[6]  M. McHenry,et al.  Structure and magnetic properties of SmCo7−xZrx alloys (x=0–0.8) , 1998 .

[7]  Jianli Wang,et al.  Magnetic properties of Y(Fe,M)10Si2 compounds (M=Fe, Ni, Co and Mn) , 1997 .

[8]  Weihua Tang,et al.  Crystal structure and magnetism of LaCo13−x−yFexSiy compounds , 1996 .

[9]  N. Phuc,et al.  Magnetic properties of the Ce(Co 1- x Fe x ) 4B compounds , 1995 .

[10]  S. Shaheen,et al.  Magnetic properties of Y(Fe,Co)10Mo2 alloys , 1994 .

[11]  N. Hong,et al.  Effects of iron substitution on the magnetic anisotropy of YCo4B , 1991 .

[12]  N. Hong,et al.  Magnetic anisotropy of the Y2(Co1 − xFex)14B intermetallic compounds , 1989 .

[13]  N. Hong,et al.  Magnetic anisotropy of the Y(Co1-xFex)3 pseudobinary compounds , 1989 .

[14]  I. Creangă,et al.  Magnetic properties of YCo4‐xFexB compounds , 1989 .

[15]  G. Hadjipanayis,et al.  Magnetic properties of rare-earth transition-metal borides , 1988 .

[16]  N. Hong,et al.  Individual site magnetic anisotropy of the iron and cobalt ions in rare earth-iron and rare earth-cobalt intermetallic compounds , 1988 .

[17]  R. L. Streever Individual Co site contributions to the magnetic anisotropy of RCo 5 compounds and related structures , 1979 .

[18]  J. Shah,et al.  Neutron diffraction study of the Th(Co 1-x Fe x ) 5 alloys , 1973 .

[19]  K. Buschow,et al.  Composition and crystal structure of hexagonal Cu-rich rare earth–copper compounds , 1971 .