Dynamic and kinetic properties of point defects in γ U-10Mo: a molecular dynamics study

Abstract

Controlled defects population and their movement constitute the foundation for describing micro-structural evolution in any material systems for nuclear applications. Molecular dynamics (MD) simulations were performed to study temperature (1200–1400 K) dependent displacement cascades with a U primary knock on atom (pka) carrying 2 keV kinetic energy in γ U-10Mo. We observed a strong impact of the temperature on the population of point defects. The impact of kinetic energy of the pka on the number of survived and maximum point defects is addressed carefully where an increase in the number of defects led to an increase in the energy. Nudged elastic band (NEB) calculations were involved to calculate the activation energies of self-interstitial Mo for different intra and inter-planar transitions. The transitions between 〈011〉 to 〈011〉, 〈001〉 to 〈011〉, 〈001〉 to 〈111〉, 〈111〉 to 〈001〉 and 〈111〉 to 〈110〉 Mo-Mo dumbbell configurations were explored. The impact of applied strains on the activation energy in each case of the transitions was investigated where irregular behavior in the energy with rise in the strain was observed.