Y. Zayachuk N. Catarino C. Smith I. Jepu C. Ayres A. Widdowson E. Alves M. Rubel JET contributors
Beryllium samples from the JET ITER-like wall limiter tiles with either co-deposits or surface cracks caused by melt damage, were immersed into boiling water for 4 h 15 min to simulate and assess the impact of coolant water ingress into a tokamak on the state of Be components. Microscopy of the water-treated surfaces and the residue in the water re…
Preprint 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 PublishedAlexander J. Leide Matthew J. Lloyd Richard I. Todd David E. J. Armstrong
Raman spectroscopy has been used to identify defective bonding in neon and silicon ion irradiated single crystals of 6H-SiC. Observable differences exist in the CC bonding region corresponding to different defect structures for neon and silicon ion implantations. Evidence of oxidation during high temperature ion implantation is observed as C-O a…
PreprintAlexander J. Leide Richard. Todd David E. J. Armstrong
Focussed ion beam (FIB) milling can be used to reveal sub-surface fracture and deformation below indents in materials. However, evolution of residual stresses around the indent impression cause changes to the crack morphology during the FIB cross-sectioning procedure. Berkovich nanoindents in single crystal hexagonal (6H) silicon carbide cause r…
PreprintGeorge Fulton Artem Lunev
Tungsten, a plasma-facing material for future fusion reactors, may be exposed to air during abnormal operation or accidents. Only limited information is available on the evolution of related oxide phases. This work addresses the effect of substrate orientation on structural variations of tungsten oxides. Annealing experiments in an argon-oxygen atm…
Preprint PublishedJ.E. Menard T. Brown L. El-Guebaly M. Boyer J. Canik B. Colling R. Raman Y. Zhai P. Buxton B. Covele C. D'Angelo A. Davis S. Gerhardt M. Gryaznevich M. Harb T.C. Hender S. Kaye D. Kingham M. Kotschenreuther S. Mahajan R. Maingi E. Marriott E.T. Meier L. Mynsberge C. Neumeyer M. Ono S.A. Sabbagh V. Soukhanovskii P. Valanju R. Woolley
A Fusion Nuclear Science Facility (FNSF) could play an important role in the development of fusion energy by providing the nuclear environment needed to develop fusion materials and components. The spherical torus/tokamak (ST) is a leading candidate for an FNSF due to its potentially high neutron wall loading and modular configuration. A key consid…
Preprint PublishedR. Scannell M. Beurskens M. Kempenaars G. Naylor M. Walsh T. O’Gorman R. Pasqualotto
Absolute calibration of LIDAR Thomson scattering systems on large fusion devices may be achieved using rotational Raman scattering. The choice of calibrating gas molecule presents different options and design trade-offs and is likely to be strongly dependent on the laser wavelength selected. Raman scattering of hydrogenic molecules produces a very …
PublishedR. Scannell M. J. Walsh P. G. Carolan N. J. Conway A. C. Darke Et Al
A new edge Thomson scattering diagnostic has been implemented at MAST to complement an existing high spatial resolution ruby laser system and the high time sampling core Nd:YAG system. The Nd:YAG system comprises of four independently controllable lasers. Scattered light from these lasers is viewed at large scattering angle 153° by a special optic…
Published