Abstract
Iron-rare earth, Nd, Gd or Tb, alloy powders with the eutectic compositions were produced by using centrifugal atomization. The shapes, surface structures and cross sections of the powders were observed microscopically. Oxygen and nitrogen content were analysed at each sieved size. The obtained fine powder under 100 μm was almost spherical, while many worm-like-shaped particles were observed in the coarser powders with diameters of above 100 μm. The Fe–Nd powder had a smooth surface, and its oxygen content decreased with increase in powder size. The surface of Fe–Gd and Fe–Tb powders were covered with finely wrinkled surfaces. Many gooves were observed on the surfaces of the Fe–Gd powder and the coarser Fe–Tb powder. Fine microstructure without segregation was obtained in the powder having diameters of under 100 μm. The grain size decreased with decrease in particle size.
