2001 年 42 巻 4 号 p. 670-673
Glass-forming ability and low field magnetic properties of Nd50Fe40Si10−xAlx (x=0–10) melt-spun ribbons and cast rods are investigated in the temperature range 5–600 K . The dependence of the coercive field on the thickness and preparation method is ascribed to the existence in the amorphous matrix of very small Fe–Nd-based ferromagnetic clusters, which can not be detected by XRD measurements, the size of which approaches to a single magnetic domain. Coercivity increases substantially at reduced temperatures even in low fields. The development in Nd–Fe-based bulk amorphous alloys of two different types of magnetic order, i.e. short-range spin-glass-like order and long-range ferromagnetic order is revealed by zero-field-cooled and field-cooled magnetization measurements.