Damage production in atomic displacement cascades in beryllium

Abstract

The paper presents the results of a molecular dynamics simulation of cascade damage production in beryllium caused by self-ion recoils in the energy range of 0.5–3keV. It is demonstrated that point defects are produced in Be preferentially in well-separated subcascades generated by secondary and higher order recoils. A linear dependence of the point defect number on the primary recoil energy is obtained with the slope that corresponds to formal atom displacement energy of ∼21eV. Most of the damage is created as single defects and the relatively high part of created point defects (∼50%) survives the correlated recombination following the ballistic cascade stage and becomes freely-migrating.

Keywords

• Beryllium
• Cascade
• Simulation
• Molecular dynamics