The development of U-7Wt%Mo for large particle powders by centrifugal atomization

In order to reduce the extensive diffusion reaction between fuel particle and Al matrix during irradiation of U-Mo dispersion fuel, large spherical particle powder of U-7wt.%Mo alloy with small specific surface areas could be fabricated by utilizing centrifugal atomizing method in KAERI. Large spherical particles of U-7wt.%Mo alloy raging from 100 to 700 were obtained higher than 95% in yield, by adjusting the process parameters. The revolution speed of the rotating disk and the portion of He gas in cooling gases are effective process parameters for the fabrication of large spherical U-Mo powder. The atomized U-Mo alloy powder showed a relatively uniform distribution and a near-perfect spherical shape. The atomized powder irrespective of particle size was generally found to have single phase γ-phase with isotropic structure with columnar structure around the periphery and equiaxed structure interior the particle. (author)