A. De Backer C. Domain C.S. Becquart L. Luneville D. Simeone A. E. Sand K. Nordlund
The impacts of ions and neutrons in metals causes cascades of atomic collisions that expand and shrink, leaving microstructure defect debris, i.e. interstitial or vacancy clusters or loops of different sizes. In [A. De Backer, A. E. Sand, K. Nordlund, L. Lun´eville, D. Simeone, and S. L. Dudarev. EPL, 115(2):26001, 2016.], we described a method…
Preprint PublishedI. Rovelli S.L. Dudarev A.P. Sutton
The evolution of the defect microstructure in materials at high temperature is dominated by diffusion-mediated interactions between dislocations, vacancy clusters and surfaces. This gives rise to complex non-linear couplings between interstitial and vacancy-type dislocation loops, cavities and the field of diffusing vacancies that adiabatically …
Preprint PublishedA. Hollingsworth M.-F. Barthe Z. Hu P. Desgardin M.Yu. Lavrentiev S.L. Dudarev P. Derlet D. Mason J. Hess S. Davies B. Thomas H. Salter E.F.J. Shelton K. Heinola K. Mizohata A. De Backer A. Baron-Wiechec I. Jepu E. Zayachuk A. Widdowson E. Meslin A. Morellec
Self-ion bombardment of pure tungsten with ion energies of 2 MeV is used to mimic the defects created by neutrons in a fusion reactor. Electron microscopy is used to characterize the microstructure of samples. Thermal Desorption Spectrometry (TDS) is performed on deuterium implanted samples in order to estimate deuterium inventory as function of…
Preprint PublishedH. Wilcox B. Lewis P. Styman
Small and shear punch testing are promising techniques that can be applied as virtually non-destructive tools to monitor in-service components and maximise the amount of information that can be obtained from limited in situ material; several mechanical properties can be determined at critical locations of a component with no need for repair welds. …
Preprint PublishedV.D. Vijayanand M. Mokhtarishirazabad J. Peng Y. Wang M. Gorley D.M. Knowles M. Mostafavi
Determining tensile properties from small punch test is being pursued actively in the nuclear industry due to the limited volume of material such tests use compared with standard tests which can be critical when considering active or development samples. One of the crucial challenges in harnessing the full potential of this technique is formulat…
Preprint PublishedM.R. Gilbert L.W. Packer T. Stainer
Molybdenum is a potential material for future nuclear fusion experiments and power plants. It has good thermo-mechanical properties and can be readily fabricated, making it attractive as an alternative material to tungsten (the current leading candidate) for high neutron flux and high thermal load regions of fusion devices. Unfortunately, exposu…
Preprint PublishedS.A. Sabbagh J.W. Berkery Y.S. Park J.H. Ahn Y. Jiang J.D. Riquezes J.G. Bak R.E. Bell M.D. Boyer L. Delgado-Aparicio A.H. Glasser J. Hollocombe J. Kim A. Kirk J. Ko W. Ko L. Kogan B.P. LeBlanc J.H. Lee C.E. Myers L. Terzolo A. Thornton S.W. Yoon
Disruption prediction and avoidance is a critical need for next-step tokamaks such as ITER. The Disruption Event Characterization and Forecasting Code (DECAF) is used to fully automate analysis of tokamak data to determine chains of events that lead to disruptions and to forecast their evolution allowing sufficient time for mitigation or full av…
Preprint PublishedFrancesco Paolo Orsitto Michele Romanelli
Similarity experiments are conceived to study on existing tokamak facilities, characteristics of scenarios found on other devices or planned for new machines. The possibility of doing similarity experiments is linked to the physics processes studied and it gives in any case partial views which can be found in integrated way only on the planned d…
Preprint PublishedL C Appel S Kwak F Militello J Svensson
A novel approach using Bayesian inference has been implemented to interpret the filamentary dynamics measured by a Langmuir probe fixed to a reciprocating assembly on MAST. The model describes the system as a superposition of time-displaced filaments and a fixed background component. Each filament is parameterised in terms of a characteristic rise …
Preprint PublishedD. Iglesias W. Arter I. Balboa P. Bunting C. Challis J.W. Coenen Y. Corre S. Esquembri S. Jachmich K. Krieger G.F. Matthews R.A. Pittsh V. Riccardo M.L. Richiusa M. Porton F. Rimini S. Silburn V.K. Thompson R. Otin D. Valcarcel L. Vitton-Mea Z. Vizvary J. Williams JET contributors
The JET outboard divertor targets are the in-vessel components which receive the largest heat flux density. Surface delamination, radial cracks, and tie rod failures have been observed in the outboard tungsten-coated CFC tiles, while bulk tungsten special lamellas were intentionally melted in dedicated experiments. These different types of damag…
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