Molecular dynamics simulations of high-energy displacement cascades in hcp-Zr

High-energy (up to 80 keV) displacement cascades in hcp-Zr are studied by classical Molecular Dynamics (MD) simulations. The statistics of defect production are reported and the formation of subcascades and defect clusters are analyzed. We find that the probability of subcascade formation increases along with the incident energy, and already reaches 100% at 80 keV. Our simulations also reveal that high-energy cascades could significantly promote the formation of defect clusters, sometimes even directly create experimental-scale (around 3 nm) vacancy clusters. Our research provides basic knowledge of high-energy displacement cascades in hcp-Zr, and offers a possible explanation for the low-dose irradiation experiments of Zr-based alloys.