液体急冷 Sm-Fe 合金の構造と磁性

The atomic structure and magnetic properties of melt-quenched Sm100-xFex (x=1, 10, 20, 30, and 40) alloys were studied by means of X-ray diffraction, Mossbauer spectroscopy, and magnetic measurements. For x=10, 20, 30, and 40, clusters of amorphous Sm-Fe phases are formed in an hcp-Sm matrix, and some of them behave superparamagnetically. In the thermomagnetic curves for x=10, 20, and 30, a field cooling effect was observed at temperatures less than around 160 K, which is the magnetic transition temperature of pure hcp-Sm. This effect is due to inter-cluster interaction 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.