MD simulations to evaluate effects of applied tensile strain on irradiation-induced defect production at various PKA energies

Molecular Dynamics (MD) simulations were conducted to investigate the influence of applied tensile strain on defect production during cascade damages at various Primary Knock-on Atom (PKA) energies of 1–30 keV. When 1% strain was applied, the number of surviving defects increased at PKA energies higher than 5 keV, although they did not increase at 1 keV. The rate of increase by strain application was higher with higher PKA energy, and attained the maximum at 20 keV PKA energy with a subsequent gradual decrease at 30 keV PKA energy The cluster size, mostly affected by strain, was larger with higher PKA energy, although clusters with fewer than seven interstitials did not increase in number at any PKA energy.

► Strain effects on defect formation were evaluated at various PKA energies by MD.
► Radiation-induced defects were increased numerically by external strain.
► Enhanced formation of larger clusters causes the numerical increase of defects.
► Strain influence on the number of defects was greatest at about 20 keV PKA.
► Cluster size, which is mostly affected by strain, was greater with higher PKA energy.