Dominic C Calleja Wayne Arter Marco De-Angelis Edoardo Patelli
Nuclear fusion, the process by which the Sun generates energy, is proposed as one solution to secure the future of global energy supply. If successful it will provide an unlimited source of clean energy. Probably the most promising approach to harnessing fusion for energy production is that of the Tokamak device, a magnetic confinement device of to…
PublishedMikhail Yu. Lavrentiev Chu-Chun Fu Frédéric Soisson
We report a theoretical study of microstructure, magnetic properties, and their relationship in relatively concentrated Fe-Cr alloys in both Fe- and Cr-rich regions. Annealing of initially random systems at 500° C for times of the order of 106 s substantially changes their microstructure. In both systems, solute atoms form clusters with…
Preprint PublishedArtem Lunev Robert Heymer
The laser flash method is highly regarded due to its applicability to a wide temperature range, from cryogenic temperatures to the melting point of refractory metals, and to extreme environments involving radioactive or hazardous materials. Although instruments implementing this method are mostly produced on a commercial basis by major manufactu…
Preprint PublishedMax Boleininger Sergei L. Dudarev
Linear elasticity theory predicts a divergent strain field at the dislocation core, resulting from the continuum approximation breaking down at the atomic scale. We introduce a minimum model that includes elastic interactions and discrete lattice periodicity, and derive a set of equations that treat the core of an edge dislocation from a solely geo…
Preprint PublishedR.G. Abernethy J.S.K.-L. Gibson A. Giannattasio J.D. Murphy O. Wouters S. Bradnam L.W. Packer M.R. Gilbert M. Klimenkov M. Rieth H.-C. Schneider C.D. Hardie S.G. Roberts D.E.J. Armstrong
Only limited data exist on the effect of neutron irradiation on the brittle to ductile transition (BDT) in tungsten. This work investigates the increase in brittle to ductile transition temperature (BDTT) following neutron irradiation to 1.67 displacements per atom, using four-point bend tests over a range of temperatures (623 – 1173 K) and strai…
Preprint PublishedDaniel R. Mason Duc Nguyen-Manh Mihai-Cosmin Marinica Rebecca Alexander Sergei L. Dudarev
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 PublishedYang Li Max Boleininger Christian Robertson Laurent Dupuy Sergei L Dudarev
Body-centered cubic metals and alloys irradiated by energetic particles form highly mobile prismatic dislocation loops with a/2 {111} -type Burgers vectors. We show how to simulate thermal diffusion of prismatic loops using a discrete dislocation dynamics approach that explicitly includes the stochastic forces associated with ambient thermal fluctu…
Preprint PublishedMatthew J. Lloyd Robert G. Abernethy Mark R. Gilbert Ian Griffiths Paul A. J. Bagot Duc Nguyen-Manh Michael P. Moody David E. J. Armstrong
High temperature, neutron irradiated single crystal tungsten, with a post irradiation composition of W-1.20±0.11at.%Re-0.11±0.05at.%Os-0.03±0.01at.%Ta was characterised using a combination of Atom Probe Tomography (APT) and Scanning Transmission Electron Microscopy (STEM). APT showed that within nanoscale clusters of Re/Os, the atomic density wa…
Preprint PublishedA. Hollingsworth M. Yu. Lavrentiev R. Watkins A. Davies S. Davies R. Smith D. R. Mason A. Baron-Wiechec Z. Kollo J. Hess I. Jepu K. Heinola J. Likonen K. Mizohata E. Meslin M.-F. Barthe A. Widdowson I. S. Grech K. Abraham A. McShee Y. Martynova M. Freisinger A. De Backer
A new facility to study the interaction of hydrogen isotopes with nuclear fusion relevant first wall materials, its retention and release, has been produced. The new facility allows implanting a range of gases into samples, including tritium. Accurate study of isotope effects, such as the isotopic exchange in damaged microstructure, has previously …
Preprint PublishedPui-Wai Ma S. L. Dudarev
CALANIE (CALculation of ANIsotropic Elastic energy) program evaluates an elastic interaction correction to the total energy of a localized object, for example a defect in a solid material simulated using an {it ab initio} or molecular statics approach, resulting from the use of periodic boundary conditions. The correction, computed using a fully el…
Preprint Published