Open AccessOn the stability and mobility of di-vacancies in tungsten
Author(s) -
K. Heinola,
Flyura Djurabekova,
T. Ahlgren
Publication year - 2017
Publication title -
nuclear fusion
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.774
H-Index - 120
eISSN - 1741-4326
pISSN - 0029-5515
DOI - 10.1088/1741-4326/aa99ee
Subject(s) - tungsten , materials science , stability (learning theory) , nuclear engineering , computer science , metallurgy , engineering , machine learning
Properties of small vacancy clusters in tungsten were studied with first-principles calculations. The binding and formation energies of the vacancy clusters increase with the cluster size. Dynamic characteristics of a di-vacancy were specified between room temperature and 700 K with lattice kinetic Monte Carlo calculations, which were parametrised with the present first-principles results for the dissociation barriers. An Arrhenius fit for the di-vacancy diffusion yielded , and for the mean lifetime, ps. The di-vacancy system was found to be stable up to 500 K, due to the high energy needed for its dissociation. Having a carbon impurity was found to increase the tungsten di-vacancy binding energy.
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