UKAEA Journals

Showing 1 - 5 of 5 Journals Results
2019
UKAEA-CCFE-PR(19)44

The low energy structures of irradiation-induced defects have been studied in detail, as these determine the available modes by which a defect can diffuse or relax. As a result, there are many studies concerning the relative energies of possible defect structures, and empirical potentials are commonly fitted to or evaluated with respect to these en…

Preprint Published
2019
UKAEA-CCFE-PR(19)37

The diffusion of defects in crystalline materials governs macroscopic behaviour in a wide range of processes, including alloying, precipitation, phase transformation, and creep. In real materials, intrinsic defects are unavoidably bound to static trapping centres such as impurity atoms, meaning that their diffusion is controlled by the de-trapping …

Preprint Published
2017
CCFE-PR(17)64

In a fusion tokamak, the plasma of hydrogen isotopes is in contact with tungsten at the surface of a divertor. In the bulk of the material, the hydrogen concentration profile tends towards dynamic equilibrium between the flux of incident ions and their trapping and release from defects, either native or produced by ion and neutron irradiation. The …

Preprint Published
2017
CCFE-PR(17)57

Quantum dynamics within solids is usually restricted to low mass particles such as electrons and muons, or single atoms of light elements such as hydrogen. In this letter we report observation of the quantum-assisted motion of self-interstitial atom clusters in tungsten (each of mass 184 Da), travelling distances of several nanometres between trapp…

Preprint
2013

We have developed empirical interatomic potentials for studying radiation defects and dislocations in tungsten. The potentials use the embedded atom method formalism and are fitted to a mixed database, containing various experimentally measured properties of tungsten and ab initio formation energies of defects, as well as ab initio interatomic forc…

Published