Reply to Murch's 'Comments on the mechanism of self-diffusion of carbon in hyperstoichiometric uranium carbide'

The correction to the D* term proposed by Murch seems important in several additional ways. First, assuming that the activation energy, ΔHsub(m), is essentially independent of the carbon-to-uranium ratio, it can be seen that the quantity [(2 - x)(x - 1)] requires that the carbon diffusivity in hyperstoichiometric uranium carbides reach a maximum value at x = 1.5. Second, inclusion of the factor (x - 1) in the preexponential term also helps to explain the low experimental D* values commonly observed for slightly hyperstoichiometric compositions. (Auth.)