Evolution of Threshold Displacement Energy in Irradiated Graphite

Abstract

For nuclear reactors, the value of the threshold displacement energy ${E}_{d}$ of graphite is an important quantity in the calculation of irradiation damage. Using atomistic simulations, this study quantifies the evolution of ${E}_{d}$ with dose by calculating displacement probabilities for pristine and irradiated graphite. An overall trend of decreasing ${E}_{d}$ with increasing irradiation dose is found, indicating that current dose estimates in reactor applications may $u\phantom{\rule{0}{0ex}}n\phantom{\rule{0}{0ex}}d\phantom{\rule{0}{0ex}}e\phantom{\rule{0}{0ex}}r\phantom{\rule{0}{0ex}}e\phantom{\rule{0}{0ex}}s\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}m\phantom{\rule{0}{0ex}}a\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}e$ the degree of damage accumulated over a reactor's lifetime.