On the Magnetic Behaviour of Dy sub 15 Fe sub 77 C sub 8 Pseudoternary Alloys

Polycrystalline samples with nominal composition of Dy sub 15 Fe sub 77 (B sub 1--x C sub x ) sub 8 with 0 < = x < = 1 and Dy sub 15 (Fe sub 1--y Co sub y ) sub 77 C sub 8 with 0 < = y < = 0.5 were prepared by arc melting under a high purity Ar atmosphere. The main results are: (1) the coercive field is strongly enhanced with the Carbon content: for x = 1 the sub i H sub c value is 17 kOe at room temperature; (2) at 4.2K a very low coercive field is measured in respect that it is both measured at 300 and 77K; and (3) the cobalt substitution increases the Curie temperature (for y = 0.5 the T sub c value is equal to 675 deg C) and for y = 0.2 the saturation magnetization exhibits the maximum value. Graphs. 14 ref.--AA