URANIUM DIOXIDE SINTERED BODY AND METHOD FOR PRODUCING THE SAME

摘要

<P>PROBLEM TO BE SOLVED: To provide a uranium dioxide sintered body having a large average grain size and high sintered body density and a method for producing the same. Ž<P>SOLUTION: The method for producing the uranium dioxide sintered body having sintered body density of ≥99.5% TD (theoretical density) and an average crystal grain size of ≥30 μm includes: bringing uranium fluoride into a vapor phase reaction with ammonia gas and water vapor to produce ADU (ammonium diuranate) powder; separating hydrogen fluoride gas generated as a by-product; washing the ADU powder, converting it to spherical ADU powder having residual fluorine concentration of ≤1% by spray drying; converting the spherical ADU powder to uranium dioxide powder having an angle of repose of ≤40° by roasting reduction; and molding and sintering the uranium dioxide powder. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž