Volume interdiffusion coeffcient and uncertainty assessment for polycrystalline materials

Abstract

A method has been developed in order to assess small volume interdiffusion coeffcients from experimental Electron Probe MicroAnalysis concentration profiles of polycrystalline materials by means of Boltzmann-Matano or den Broeder methods and their complementary Hall method. These methods have been used as tools for the investigation of the quasi-binary UO₂/U_(1-y)Pu_yO_(2-z) interdiffusion, for which obtaining a solid solution in the bulk of grains is of major interest. In this paper uncertainties on the interdiffusion coefficient as a function of concentration have been computed for each method. Small volume cofficient measurements were enhanced by means of a small angle acquisition profile line with respect to the interdiffusion interface.