Magnesiothermic reduction process applied to the powder production of U(Mo) fissile particles
Résumé
Uranium-molybdenum alloy powders are obtained by a new synthetic route deriving from the Kroll process which avoids a "melting-solidification" step. This alternative process consists in the redn. of uranium dioxide by magnesium in presence of Mo in a sealed Mo crucible heated at temps. ranging from 750 to 1100 °C for dwell periods ranging from 12 to 48 h. An appropriate quenching allows the retention of the high temp. bcc-form $\gamma$-U(Mo). The side products are easily removed by a soaking into a dild. hydrochloric acid soln. under sonication. The agglomerates have a typical size in the range 10-200 μm, with an irregular shape. They display even at the periphery equiaxed grains with homogeneous distribution of Mo. Small closed porosity, which seems to be preferentially located at the grain boundaries corresponds to roughly 2% of the vol. fraction. [on SciFinder(R)]