The magnetic and structural properties of the high-coercivity Nd50Fe40Al10 amorphous alloys

Melt-spun amorphous ribbons with thicknesses between 25 and 150 μm and amorphous rods with diameters between 0.5 and 2 mm, prepared by copper mould suction casting, having nominal composition Nd50Fe40Al10, were measured. The magnetic properties were measured as a function of temperature from 5 to 800 K. The dependence of the coercive field on the thickness of the samples and temperature is ascribed to two magnetic phases: Fe–Nd ferromagnetic clusters and a Nd-based matrix. The differences observed between zero-field-cooled (MZFC) and field-cooled (MFC) magnetisations as well as the presence of a cusp on the MZFC curve, and its displacement as a function of the magnitude of the external field are consistent with two types of magnetic order: spin-glass-like short-range order and long-range ferromagnetic order.