Status of Diffusion-Controlled Graphite Oxidation Studies for High Temperature Gas-Cooled Reactors

Abstract

This document summarizes current status of graphite oxidation studies from several points of view. They include (i) selection and qualification of materials using standard test methods; (ii) understanding the mechanisms and the effects of oxidation using materials science methods; (iii) designing experiments and obtaining reliable information on reaction kinetics and transport properties involved in graphite oxidation; and (iv) using these data for updating and/or developing complex computer codes to be used as tools for simulation and prediction of oxidation effects. The report emphasizes the importance of diffusion-controlled oxidation and its dependence of material and process related parameters which makes it difficult to develop integrated simulation models. The last section contains a short overview of issues not solved yet which make necessary more continuation of experimental and modeling activities on nuclear graphite oxidation.