Jacob Chapman Pui-Wai Ma Sergei Dudarev
Fundamental flaws in the Heisenberg Hamiltonian are highlighted in the context of its application to BCC Fe, including the particular issues arising when modelling lattice defects. Exchange integrals are evaluated using the magnetic force theorem. The bilinear exchange coupling constants are calculated for all the interacting pairs of atomic ma…
PublishedArtem Lunev Vadim Zborovskii Teymur Aliev Robert Heymer Olga Vilkhivskaya
PULsE (Processing Unit for Laser Flash Experiments) is a software suite for processing data generated by a variety of laser flash analysis instruments. It is highly customisable and allows adjusting to the finest experimental detail, including but not limited to electromagnetic interferences, non-uniform laser heating and detection, and coupled …
PreprintD. Nguyen-Manh J.S. Wrobel M. Klimenkov M.J. Lloyd L. Messina S.L. Dudarev
Understanding how properties of materials change due to nuclear transmutations is a major challenge for the design of structural components for a fusion power plant. In this study, by combining a first-principles matrix Hamiltonian approach with thermodynamic integration we investigate quasisteady state configurations of multi-component alloys, …
PreprintGreg Bailey Mark Gilbert Olga Vilkhivskaya
The public perception of fusion power is that it will provide a clean source of abundant nuclear energy. This is not wholly accurate. Currently planned fusion reactors will use the deuterium-tritium (DT) reaction for power generation. This reaction produces 14 MeV neutrons which, as they cannot be magnetically confined, impinge upon the reactor str…
PreprintJan Fikar Robin Schaeublin Daniel R. Mason Duc Nguyen-Manh
The vacancies produced in high energy collision cascades of irradiated tungsten can form vacancy clusters or prismatic vacancy dislocation loops. Moreover, vacancy loops can easily transform into planar vacancy clusters. We investigated the formation energies of these three types of vacancy defects as a function of the number of vacancies using thr…
PublishedCarmen Makepeace
Fuel retention in the JET-ITER like wall (JET-ILW) has decreased by a factor of 20 compared to operation with a carbon wall [1]. The reduction in retention is due largely to the decrease in chemical erosion of the beryllium main chamber. A reduction in co-deposition of fuel with beryllium has previously been reported in the divertor [2]. However…
Preprint PublishedS. Von Tiedemann D Collins M. Gilbert I. Kodeli
Predictions of material activity in commercial fusion conditions predominantly rely on computational methods, due to a lack of data on long-term e ects of high-energy neutron irradiation on structural steels. Consequently, this could result in a bias due to uncertainties in nu…
Preprint PublishedJ. B. J. Chapman P. -W. Ma
A machine-learned spin-lattice interatomic potential (MSLP) for magnetic iron is developed and applied to mesoscopic scale defects. It is achieved by augmenting a spin-lattice Hamiltonian with a neural network term trained to descriptors representing a mix of local configuration and magnetic environments. It reproduces the cohesive energy of BCC…
PreprintChris Hardie Rhys Thomas Yang Liu Philipp Frankel Fionn Dunne
Classical crystal plasticity formulation based on dislocation slip was extended to include the mechanisms of dislocation channelling, with associated strain softening which is observed in many alloys post irradiation. The performance of the model was evaluated against experimental data on Zircaloy-4, which included engineering stress-strain respons…
Preprint PublishedO. El Atwani H.T. Vo M. Tunes C. Lee A. Alvarado N. Krienke J. Poplawsky A.A. Kohnert J. Gigax W.-Y. Chen M. Li Y. Wang J.S. Wróbel Duc Nguyen-Manh J.K.S. Baldwin U. Tukac E. Aydogan S. Fensin E. Martinez
In the quest of new materials that can withstand severe irradiation and mechanical extremes for advanced applications (e.g. fission reactors, fusion devices, space applications, etc), design, prediction and control of advanced materials beyond current material designs become a paramount goal. Here, though a combined experimental and simula…
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