M. R. Gilbert S. Zheng R. Kemp L. W. Packer S. L. Dudarev J.-Ch. Sublet
A key goal for fusion materials modelling research is the development of predictive simulation models and capabilities to assess material performance under the neutron irradiation conditions expected in near-plasma regions of fusion reactor tokamaks. This paper presents computational results from the modelling of neutron fields in the latest concep…
PublishedM.R. Gilbert L.W. Packer J.-Ch. Sublet R.A. Forrest
The simulation of neutron irradiation–induced transmutation using inventory codes is an important part of the research into materials in various nuclear environments, including fusion, fission, medical physics, nuclear security, and astrophysics. These simulations, even in their simplest form, such as the neutron irradiation of a single pure elem…
PublishedS.L. Dudarev K. Arakawa X. Yi Z. Yao M.L. Jenkins M.R. Gilbert P.M. Derlet
Defect microstructures formed in ion-irradiated metals, for example iron or tungsten, often exhibit patterns of spatially ordered nano-scale dislocation loops. We show that such ordered dislocation loop structures may form spontaneously as a result of Brownian motion of loops, biased by the angular-dependent elastic interaction between the loops. P…
PublishedM. R. Gilbert P. Schuck B. Sadigh J. Marian
In body-centered-cubic (bcc) crystals, 1/2{111} screw dislocations exhibit high intrinsic lattice friction as a consequence of their nonplanar core structure, which results in a periodic energy landscape known as the Peierls potential UP. The main features determining plastic flow, including its stress and temperature dependences, can be derived di…
PublishedT. D. Swinburne S. L. Dudarev S. P. Fitzgerald M. R. Gilbert A. P. Sutton
Isolated kinks on thermally fluctuating 1/2 111 screw, 100 edge, and 1/2 111 edge dislocations in bcc iron are simulated under zero stress conditions using molecular dynamics (MD). Kinks are seen to perform stochastic motion in a potential landscape that depends on the dislocation character and geometry, and their motion provides fresh insight …
PublishedM.R. Gilbert S.L. Dudarev D.Nguyen-Manh L.W. Packer J-Ch. Sublet
In a fusion reactor materials will be subjected to significant fluxes of high-energy neutrons. As well as causing radiation damage, the neutrons also initiate nuclear reactions leading to changes in the chemical composition of materials (transmutation). Many of these reactions produce gases, particularly helium, which cause additional swelling and …
PublishedM-C Marinica Lisa Ventelon M R Gilbert L Proville S L Dudarev J Marian G Bencteux F Willaime
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…
PublishedL. W. Packer S. Hughes M. Gilbert S. Lilley R. Pampin
This work presents new integral data measured at the ASP 14 MeV neutron irradiation facility at Aldermaston in the UK, which has recently become available for fusion-related work through the CCFE materials programme. Measurements of reaction products from activation experiments using elemental foils were carried out using gamma spectrometry in a hi…
Published