Magnetic properties and structure of melt-quenched Sm-Fe alloys

The atomic structure and magnetic properties of melt-quenched Sm100-xFex (x = 1, 10, 20, 30, 40) alloys were studied by means of X-ray diffraction, Moessbauer spectroscopy, and magnetic measurements. For x = 10, 20, 30 or 40, clusters of amorphous Sm-Fe phases are formed in a hcp Sm matrix. Some of these behave superparamagnetically. The thermomagnetic curves for x = 10, 20, 30 samples exhibited a field cooling effect at temperatures less than 160 K, which is the magnetic transition temperature of pure hcp Sm. This effect is due to inter-cluster interactions induced by magnetic ordering in the hcp Sm matrix. For x = 1, Fe atoms are dissolved in the Sm matrix and their magnetic moments are very small