Crystal structure and magnetic properties of SMCo7-xAGx

The SmCo7-xAgx (x = 0.1,0.2,0.5) bulk samples are prepared by are melting. X-ray powder diffraction indicates that as-cast alloys SmCo7-xAgx with x = 0.1 and 0.2 crystallize in the TbCu7-type structure with the space group P6/mmm. The samples were annealed for 2 weeks at 600 degrees C, annealing induces the decomposition of the SmCo 1:7 phase (SmCo 1:7 -> SmCo 1:5+SmCo 2:17). The annealed samples were measured by a SQUID magnetometer with maximum field of 5 kOe. The derived anisotropy field at 5 K is about 213 kOe for x = 0.2 and about 182 kOe for x = 0.5. The saturation at 5 K is 103 emu/g for x = 0.2 and 145.6 emu/g for x = 0.5. The increase of x causes the decrease of magnetic anisotropy field and the increase of saturation moments. (c) 2006 Elsevier B.V. All rights reserved.