Investigation of the temperature effect on the primary radiation damage near the grain boundary in tungsten using Molecular dynamics simulations

Molecular dynamics simulations of irradiated defect clusters evolution in different crystal structures

“…The truncation radius of the vacancy cluster is the second nearest neighbor (2NN) distance and the truncation radius of the interstitial cluster is the third nearest neighbor (3NN) distance [5]. And calculation of defect formation rate: The results in figure 7 also show that the rate of vacancy cluster formation increases with increasing PKA energy, which is in general agreement with the results of the simulations of Björkas et al [22] for V and Selby et al [23] suggested that for refractory metals with higher melting points, the faster movement of the recrystallisation leading edge due to the 'hot peak' effect results in a lower vacancy cluster fraction.…”

“…On larger time scales, these stable surviving defects will migrate, combine and evolve into complex defect clusters (e.g., voids, clusters, etc), producing critical damage such as irradiation swelling, hardening, embrittlement, etc, ultimately leading to degradation of alloy material properties, which are known as the main threats to the stability of material mechanical properties and important triggers of reactor material failure [3,4]. At low temperatures and irradiation doses (irradiation damage intensity in dpa denoting the average number of atomic dislocations), the predominant defect type in fcc materials is lamellar dislocation tetrahedra, whereas in bcc materials the predominant defect is dislocation rings; at higher temperatures and irradiation doses (higher irradiation damage intensity), the defects are usually in the form of voids [5]. Therefore, an in-depth understanding of the microscopic mechanisms between the generation and evolution of irradiation defects is important for the further optimisation and design of structural materials for nuclear reactors.…”

Surface thermodynamics of yttrium titanate pyrochlore nanomaterials

“…, hardening, embrittlement, swelling) and limit the lifetime of the nuclear waste host. 45,46 Thus, predicting radiation response is critical in evaluating candidate waste forms. Previously, radiation resistance was found to be controlled by composition, 47–50 vacancy inclusion, 51,52 intrinsic disorder, 53–55 and grain size.…”

“…29,39,42 Radiation, such as β-decay of fission products and α-decay of the actinide elements, can induce point defects (e.g., interstitials and vacancies) that are aggregated for long-range disorder, 32,[43][44][45] which can further cause significant degradation to the material properties (i.e., hardening, embrittlement, swelling) and limit the lifetime of the nuclear waste host. 45,46 Thus, predicting radiation response is critical in evaluating candidate waste forms. Previously, radiation resistance was found to be controlled by composition, 47-50 vacancy inclusion, 51,52 intrinsic disorder, [53][54][55] and grain size.…”