Molecular dynamics simulation of the diffusion behaviour in Ti–Ag using diffusion couple method
Year: 2024
Type: article
Abstract: The diffusion behaviour of the Ti–Ag system was investigated using classical molecular dynamics by simulating a diffusion couple at various temperatures. One bulk of the diffusion couple consisted of titanium atoms arranged in a hexagonal close-packed (hcp) structure, i.e., 𝛼 -Ti, and the other consisted of silver atoms arranged in a face-centred cubic (fcc) structure. The modern second nearest-neighbour modified embedded-atom method (2NN-MEAM) interatomic potential was used. The mean square displacement (MSD) of Ti atoms diffusing into Ag and Ag atoms into 𝛼 -Ti was recorded during the simulation. Diffusion coefficients were determined from the slopes of lines fit to linear regions of MSD dependence on time. The Arrhenius relation was used to determine the activation energy and the frequency of attempts. The activation energy of Ti was 0 . 6 1 e V and frequency of attempts 1 . 9 0 ⋅ 1 0 − 8 m 2 s − 1 . The determined activation energy of Ag and frequency of attempts were not considered reliable because the Ag diffusion coefficient did not grow exponentially with temperature. Ti atoms penetrated deeper and greater amounts into Ag than Ag into 𝛼 -Ti and also had a greater diffusion coefficient at all temperatures. The results were compared with the available experimental data, and for these purposes, self-diffusion in 𝛼 -Ti and Ag was further investigated. Finally, it was determined that Ag diffuses in 𝛼 -Ti by hopping over interstitial positions and Ti in Ag via vacancies.
Source: Results in Physics
Authors: Šimon Svoboda, Miroslav Lebeda, Petr Vlčák, Zuzana Budinská, Jan Drahokoupil
Institution: Czech Technical University in Prague
Language: English
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,690
Award: G3663955765
OpenAlex ID: W4402038932