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.

KEYWORDS:

• MD
• γ U-10Mo
• OVITO
• point defects
• high temperature

Data availability

Data is not shared because information based on data is already available in the paper.

Disclosure statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Additional information

Funding

This research work was supported by China Scholarship Council (CSC).

Notes on contributors

Asmat Ullah

Asmat Ullah is a doctoral student in the college of nuclear science and technology, Harbin Engineering University, China. He has a number of publications and hand on experience on irradiation related phenomenon. He uses experimental and computational resources to see the impact of irradiation on different properties of materials.

Qingyu Wang

Professor Dr. Qingyu Wang is a specialist in nuclear materials. He is working both computationally and experimentally in order to have access to characteristics of materials before and after some physical treatments in a nuclear reactor environment.

Yushou Song

Professor Dr. Yushou Song is working on different domains such as nuclear physics, Monte Carlo simulations, non destructive assay etc. Currently he is working as a research director in the college of nuclear science and technology, Harbin Engineering University, China.