In situ X-ray diffraction study on structural changes of neutron-irradiated highly oriented pyrolytic graphite under high-temperature compression and decompression

Abstract

In this study, we focused on the peak of the graphite (002) [G(002)] plane of neutron-irradiated highly oriented pyrolytic graphite (HOPG) using in-situ X-ray diffraction method and analyzed the structural change during the compression and decompression processes at high temperature in order to understand the details of the transformation mechanism of neutron-irradiated HOPG. It was found that the G(002) peak can be represented by two components from RT to about 600°C, and it can be represented by only one component at the higher temperature in the neutron-irradiated sample, whereas it can be represented by only one component in the unirradiated sample.