Magnetic Properties of Sm₂(CO_1−xAl_x)₁₇

Abstract

Magnetic properties of Sm₂(Co_1−xAl_x)₁₇ powders with 0≤x≤0.12 have been investigated at room temperature. The crystal structure of these alloys is of the rhombohedral Th₂Zn₁₇ type. The lattice constants a and c were found to increase monotonically with x. The magnetization curves of aligned-powder pellets shows that the decrease of the saturation moment is stronger than that expected for a model of simple dilution of Co moments with non-magnetic Al. In the whole range of x studied these alloys have a magnetically easy c-axis. Approximate values of the anisotropy field and the anisotropy constant were estimated from the magnetization curves. The former increases slightly with x and the latter decreases. Curie temperatures of the alloys were determined by the magnetization-temperature curve measured with a magnetic balance.