The dimensional changes of highly-oriented pyrolytic graphite irradiated with fast neutrons at 430°C and 600°C

Abstract Samples of highly oriented graphite heat-treated to final temperatures of 2,000, 2,200, 2,400, 2,800 and 3,000°C have been successively irradiated with fast neutrons at controlled temperatures of 430° and 600°C in the PLUTO Materials Testing Reactor. The dimensional changes of these samples, measured parallel and perpendicular to the deposition plane, correspond closely to those of the component crystallites parallel and perpendicular to the basal planes. The changes are found to agree well with expectation from current theories of irradiation damage.