Structural and Magnetic Properties of Sm$_3$(Fe$_1-rm x$Co$_rm x$)$_27.7$Ti$_1.3$

The structure and magnetic properties of Sm
₃
(Fe
_1-x
Co
_x
)
_27.7
Ti
_1.3
compounds, with x ranging from 0 to 0.4, have been investigated by means of X-ray powder diffraction and magnetic measurements. The main phase formed was that of Nd
₃
(Fe, Ti)
₂₉
-type structure (3:29) with a relatively small amount of the ThMn
₁₂
-type structure (1:12) as a secondary phase (7-13 wt.%). The lattice parameters and the unit-cell volume decrease with increasing Co content x. It is found that substitution of Co for Fe leads to a significant increase in the Curie temperature from 488 K for x=0 to 941 K for x=0.4. Saturation magnetization gradually increases with increasing Co. All compounds show easy cone-type anisotropy