Although uranium carbides are becoming of considerable interest as nuclear fuel materials, few thermochemical data for these compounds are available and especially lack of specific heat data have made the assessment of these data unreliable. However, recently the authors made the measurement of specific heats on UC and UC2 above room temperature, and the assessment of experimental data bacame possible in some accuracy.
In this paper, the specific heat functions for UC and UC2 were derived as a function of temperature, from which the heats of formation, free energies of formation and entropies of formation of these carbides were also calculated as a function of temperature respectively. Then the assessment of these thermochemical data was carried out on the values so for reported.
In general, it was shown that the measurements at high temperatures by several authors gave a fairly good accordance with some scattering of data, which are not unreasonable in difficult experimental conditions. However, in order to make a more accurate estimation, especially for UC2, it is considered necessary to obtain further data precisely.
