Younggak Shin¹, Sanghyuk Yoo², Keonwook Kang², Byeongchan Lee¹; ¹Kyung Hee University, ²Yonsei University

Irradiation damages are often simulated with atomistic calculations but the validity depends on several factors: interatomic potentials are known to be a key factor. On the other hand, the importance of numerical setups has been underestimated. Here, we introduce the concept of a “simulation testbed.”A simulation testbed is a structured procedure from preparation of numerical samples to execution of atomistic calculations. First, we prepare numerical samples as close as possible to thin-film tungsten samples with thickness of 370 nm or less. Second, recoil events inside numerical samples are determined based on neutron-transport statistics. Third, constant-energy molecular dynamics is performed with the periodic boundary condition in the direction perpendicular to the free surface.We present the results from billion-atom molecular dynamics results of thin-film tungsten under irradiation, and compare the damages and changes in mechanical properties with experimental measurements. Further possibility of improvement is also discussed.