Study on Sintering Behavior of UO₂ Microsphere Doped with Titanium

This paper studies the preparation of titanium（Ti） UO₂ microspheres by selgol method,and its microstructure,pore distribution and grain size are observed by optical microscope,SEM and EDS.Its density is measured by water immersion method.The results show that doping small amount of titanium can significantly improve the sintering behavior at a certain sintering temperature.In this study,the optimal doping content of Ti is within 0.3% wt and the best sintering temperature is 1250-1350℃.This paper also studies the activated sintering mechanism,with a conclusion that the material transfer mechanism may enhance the cation diffusion,and residual oxygen interaction.Additionally,it studies the distribution of titanium in the microspheres.Besides the solid solution of titanium in UO₂ microspheres,the redundant enriches in the grain boundary in the form of free particles.