The role of Cu in displacement cascades examined by molecular dynamics

Primary Radiation Damage Formation

“…Although the development of alloy potentials is relatively recent, there have been a sufficient number of investigations to provide a comparison of displacement cascade evolution in pure iron with that in three binary alloys, Fe-C, Fe-Cu, and Fe-Cr. [125][126][127][128][129][130][131][132][133][134][135][136][137][138] The motivation for each of these binary systems is clear. Carbon must be added to iron to make steel, and as a small interstitial solute it could interact with and influence interstitial-type defects.…”

“…Research that began in the 1970s demonstrated that this minor impurity was responsible for a significant fraction of the observed vessel embrittlement due to its segregation into a high density of very small (a few nanometer diameter) copper-rich solute clusters (Becquart and coworkers, 126 Chapter 4.05, Radiation Damage of Reactor Pressure Vessel Steels). Becquart and coworkers employed MD cascade simulations to determine whether displacement cascades could play a role in the Cu-segregation process, for example, by coalescing with vacancies in the cascade core during the cooling phase.…”

Simulating radiation damage in a bcc Fe system with embedded yttria nanoparticles

“…In oxides the cascades can branch producing sub-cascades that form the same residual defects [6]. In metals where a vacancy-rich core around the PKA is produced together with well-separated interstitial clusters, it is only the size and number of the vacancy clusters and the interstitial loops that vary with energy [7]. The basic form of the induced radiation damage remains the same, even though interstitial loops and vacancy clusters grow bigger as the cascade energy increases.…”

“…Results in pure Fe have shown that irrespective of the PKA energy, the radiation damage after the collisional phase of the cascade consists of a vacancy rich region close to the initial PKA site surrounded by outlying interstitials, see e.g. [17,18,7]. The PKA energy determines the number of vacancies formed and the extent and size of the interstitial loops.…”

Modeling Microstructure and Irradiation Effects

“…Because of the predominant role of Cu in the embrittlement of the pressure vessel steels discovered more than 40 years ago, [75][76][77] the first simulations of displacement cascades in dilute Fe alloys were done in Fe-Cu dilute alloys. [78][79][80] Despite its notorious role in steels, the influence of C in solution was studied only recently by Calder et al [80,81] certainly because of the lack of reliable Fe-C potentials. Another interstitial species of great interest, especially in the case of materials for fusion application, is He, and its influence on the primary damage in Fe is now the subject of extensive work.…”