UKAEA Journals

Showing 1 - 10 of 12 Journals Results
2021
UKAEA-CCFE-PR(21)27

Tungsten is one the primary candidate materials for the high neutron flux, high temperature components of a future demonstrate fusion reactor. Despite this, there is a lack of data on W under fusion relevant neutron doses and irradiation temperatures. Transmutation reactions result in the production of Re and Os solute atoms, at a rate which is …

Preprint
2020
UKAEA-CCFE-PR(20)92

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…

Preprint
2020
UKAEA-CCFE-PR(20)91

Ion implantation is widely used as a surrogate for neutron irradiation in the investigation of radiation damage on the properties of materials. Due to the small depth of damage, micromechanical methods must be used to extract material properties. In this work, nanoindentation has been applied to ion irradiated silicon carbide to extract radiatio…

Preprint
2020
UKAEA-CCFE-PR(20)86

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…

Preprint
2019
UKAEA-CCFE-PR(19)51

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 Purchase
2019
UKAEA-CCFE-PR(19)42

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 Purchase
2019
UKAEA-CCFE-PR(19)22

A viable fusion power station is reliant on the development of plasma facing materials that can withstand the combined effects of high temperature operation and high neutron doses. In this study we focus on W, the most promising candidate material. Re is the primary transmutation product and has been shown to induce embrittlement through cluster fo…

Preprint Published
2017
CCFE-PR(17)05

Tungsten samples were heat-treated to achieve partial recrystallization and exposed to high ion flux deuterium plasma at different temperatures and fluences. Continuous stiffness nanoindentation measurements of near-surface hardness were performed in the grains of specific annealing states and of specific crystallographic orientation, determined by…

Preprint Published
2016

In tungsten plasma-facing fusion reactor components, Ta is the third most abundant element formed by transmutation (after Re and Os), yet little is known about the behaviour of W-Ta alloys under irradiation and any effects Ta might have on Re clustering in W-Re-Ta alloys. In this study, W-4.5 at.%Ta, W-2 at.% Re-1 at.%Ta andW-2 at.%Re alloys were e…

Published
2015

This study examines clustering and hardening in W–2 at.% Re and W–1 at.% Re–1 at.% Os alloys induced by 2 MeV W + ion irradiation at 573 and 773 K. Such clusters are known precursors to the formation of embrittling precipitates, a potentially life-limiting phenomenon in the oper- ation of fusion reactor components. Increases in hardness were …

Published