Preparation of Uranium Nitride in the Form of Microspheres

Uranium nitride microspheres were fabricated by internal gelation and carbothermic reduction. The influence of the thermal treatment and the reaction atmosphere on the chemical composition and the structural parameter of the spheres were systematically investigated. High density ( > 95% TD) spheres of 800 mu m diameter were obtained by reacting in Ar--H followed by N--H. Porous spheres with a distinct pore and grain structure and low crushing strength as feed for pellets have been fabricated in nitrogen and N-H atmosphere. Special emphasis was put on a reliable determination of N and on X-ray diffraction for the chemical composition and on the correlation of the crushing strength to structural parameters.