<p>As the basic material in reactor pressure vessel (RPV), Fe endures amounts of irradiation in the entire lifetime. Many irradiation defects such as dislocation loop are generated which affect the macroscopic mechanical properties. In this paper, we use the molecular dynamics method to investigate the effect of annealing temperature on dislocation loop strength and evolution. The annealing process contains four steps: At first, the temperature increases from room temperature (300K) to annealing temperature. The annealing temperature is set as 600K, 700K, 800K, 900K and 1000K respectively. Then the system maintains at annealing temperature for adequate time to evolve. After that, the temperature recovers to room temperature. Finally, the system evolves at room temperature to get the final configuration. The diameter of dislocation loop is 2.5<i>nm</i>. The dimension of simulation cell is defined as  with 1080455 atoms. Based on annealing simulation, we could obtain and analyze the microstructure evolution of dislocation loop. In addition, we use the tensile simulation to evaluate the strength of dislocation loop. The tensile strain is applied in the z direction on a sample studied in this work and the deformation rate is  . Here under periodic boundary conditions the system is allowed to relax in all three directions independently. Furthermore, we compare the tensile strength of the annealing and un-annealing sample. Results show that annealing temperature could improve the mechanical property of Fe to some extent.</p>

Effect of Annealing Temperature on Dislocation Loop Absorption And Evolution in Fe by Molecular Dynamics Study

Paper Proceedings: https://asmedigitalcollection.asme.org/ICONE/ICONE28/volume/85246

2021 28th International Conference on Nuclear Engineering (ICONE28)

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