Effect of oxidation on physical properties of neutron irradiated nuclear grade graphite

Effects of microstructure on the oxidation behavior of A3 matrix‐grade graphite

“…The presence of disordered carbon detected with Raman spectroscopy and observed through electron microscopy techniques may have also contributed to the low density of the specimens. It was noted, however, that the densities observed are within the expected density range for matrix graphite, which is 1.65 ± 0.15 g/cm 3,15,16 …”

“…Thermal spectrum high‐temperature gas reactors (HTGRs) rely heavily on graphite as a neutron moderator, core structural material, and component of the nuclear fuel elements due to its favorable neutronic and thermomechanical properties 1 . Although the graphite is chemically stable under normal operating conditions in an inert helium gas environment, accident scenarios including leakage of air 2 or steam can lead to oxidation and degradation of mechanical properties 3,4 . It is, therefore, of great importance to study the microstructure and oxidation behavior of nuclear graphitic materials, with the aims of building computational models to predict graphite performance during air or moisture ingress and potentially improving the fabrication process to enhance oxidation resistance and accident tolerance.…”

A multi-scale three-dimensional Cellular Automata fracture model of radiolytically oxidised nuclear graphite

“…As can be seen from The most significant changes caused by radiolytic oxidation are due to the increasing porosity content, and it has been shown by experimental data (e.g. [71]) that neutron irradiation does not have a significant effect on the pore structure and mechanical properties. Fast neutron irradiation does affect modulus and strength independently of oxidation [3].…”