【摘要】 采用内凝胶工艺,通过溶解、配胶、分散、陈化、洗涤、干燥、焙烧、还原及烧结等工序,成功制备了粒径约为650μm的UO₂微球。通过旋转粘度计测量了胶液粘度随温度、时间的变化,进而对胶液的稳定性进行了研究。研究了胶液组份的配比、胶液p H值、铀浓度及HMTA-Urea浓度对微球显微结构和性能的影响,通过体视显微镜观察了干燥后微球的表面形貌,通过SEM观察了烧结后UO₂微球的晶粒尺寸与致密化程度。通过实验得到了胶液在不同温度下的稳定时间和表观形貌完好无开裂的UO₂微球。成功地研究了适用于制备UO₂微球的稳定的内凝胶工艺技术。更多还原

【Abstract】 UO₂ microspheres with diameter ⁶50 μm were prepared by internal gelation process through dissolving, broth solution preparation, dispersing, AWD（aging, washing and drying）, calcination, reducing and sintering procedures. The broth solution viscosity changing with standing time at different temperatures was measured by rotary viscosimeter to study the broth solution stability. Effects of the composition, p H value, uranium and HMTA-Urea concentration of broth solution on the microstructure and performance of microspheres were also studied. Surface appearance of dried particles was observed by integrated microscope. Grain size and the degree of densification of UO₂ microspheres were observed by SEM. The broth solution stabilization time at different temperatures and the UO₂ microspheres with good apparent morphology have been obtained. Finally, the stable internal gelation technology for UO₂ microspheres preparation has been researched.更多还原