Cascades_ni_fenicr_zr

Final structures for Ni, FeNiCr and Zr 80 keV displacement cascades:

All classical molecular dynamics simulations were performed using the DYMOKA code (Becquart et al., 1997). The simulation box size was adapted according to the PKA energy to avoid any interaction between replicated image, as periodic boundary conditions were applied in all directions during the simulations. Since this study focuses exclusively on a PKA energy of 80 keV, the box dimensions were set to 98x98x98 unit cells (3764768 atoms) for both FeNiCr and Ni fcc materials, and to 122x152x76 unit cells (2818688 atoms) for hcp Zr.
For the simulations, the empirical interaction potentials used were derived using the Embedded Atom Method (EAM) approach. The FeNiCr potential was originally derived by Bonny et al., 2011 and hardened by Beland et al., 2017, the Ni potential was developed by Mishin, 2004 and hardened by Samolyuk et al., 2016, and the Zr potential was developed and hardened by Mendelev et al., 2007. Before simulating displacement cascades, systems were thermalized using canonical MD at 100K using velocity scaler as implemented in DYMOKA for 3ps with time step of 1fs. Once the system was equilibrated, displacement cascades were initiated in the microcanonical ensemble from different snapshots of the thermalization trajectory for up to 50ps. A single atom was selected as the PKA and assigned a kinetic energy of 80keV. The directions of the initial velocity were chosen to represent a statistically reasonable average behavior, following the approach described in Stoller et al., 1997. The timestep was dynamically adjusted between 0.005fs and 1fs during the simulations to ensure accurate energy conservation throughout the cascade events.