A study on the thermal compatibility of centrifugally atomized U-Mo and U3Si dispersion fuels

In order to investigate the thermal swelling of rod-type U-Mo and U3Si dispersion fuels, the thermal compatibility specimens prepared by centrifugally atomization method were annealed at 400 .deg. C and 450 .deg. C, and then the dimensional change and the microstructure of the specimens were examined. U-(7,8)wt.%Mo compatibility specimens showed a relatively stable volume change less than 10%, after annealing at 400 .deg. C for 1,000 hrs; however, U-6wt.%Mo and U3Si compatibility specimens exhibited an unstable volume increase more than 25%. All U-Mo and U3Si compatibility specimens showed an unstable volume increase more than 25%, after annealing at 450 .deg. C for 1,000 hrs. It is considered that the possible reason why U-Mo alloys with higher Mo content have more stable thermal compatibility with Al matrix results from a better γ-U phase metastability at high temperature