Lattice and grain-boundary diffusion of uranium in ThO2 and ThO2-UO2 solid solution

摘要: Abstract Lattice and grain-boundary diffusion of uranium in ThO2 ThO2-UO2 (1:1) solid solution were measured by using 237U as a tracer the sectioning method. The obtained penetration curves analysed according to theory for diffusion, based on an instantaneous source model. lattice coefficients D can be expressed equations: (U ThO2) = 1.10 × 10/t4 exp (− 76 400/RT) cm2/sec, D(UinThO2-UO2) 7.59 (−85 900/RT) cm2/sec. On other hand, products D' · 2a peculiar follow 2.36 10/t9 (−47 cm3/sec, ThO2-UO2) 1.04 10/t7 (−64 200/RT) where are coefficient width, respectively. results discussed connection with earlier data.