MAGNETIC-PROPERTIES OF HIGH-ENERGY BALL-MILLED AND HDDR PROCESSED ND12FE75-YCOYMO13 -LESS-THAN-OR-EQUAL-TO-Y-LESS-THAN-OR-EQUAL-TO-75) POWDERS AND THEIR NITRIDES

The magnetic properties of high-energy ball-milled (HEBM) and HDDR (hy drogenation, disproportionation, desorption, recombination) processed Nd12Fe75-yCoyMo13 (0 less than or equal to y less than or equal to 75) powders, and their nitrides, have been investigated. The ThMn12-type structure forms for Co concentrations up to at least 37 at.%. Coercivi ties of 716 kA m(-1) and 127 kA m(-1) were obtained in Nd12Fe75Mo13Nx powders prepared by HEBM and HDDR processing, respectively. For HEBM a nd nitrided powders, the partial substitution of Fe by Co results in a n increase in the Curie temperature, an increase in the saturation mag netic polarization, which passes through a maximum at y=6, and a decre ase in the coercivity.