UKAEA Journals

Showing 1 - 10 of 18 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
2021
UKAEA-CCFE-PR(21)22

In this study, radiation-induced precipitation of transmutation products is addressed via the development of a new solute and vacancy concentration dependant Ising model for the W-Re-Os system. This new model includes interactions between both Os and Re atoms, thus facilitating more representative simulations of transmutation in fusion reactor …

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
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
2015
CCFE-PR(15)27

The high-k (7 . k??i . 11) wavenumber spectrum of density fluctuations has been measured for the first time in MAST [B. Lloyd et al, Nucl. Fusion 43, 1665 (2003)]. This was accomplished with the first implementation of Doppler backscattering (DBS) for core measurements in a spherical tokamak. DBS has become a well-established and versatile diagnost…

Preprint Published
2012

Lower hybrid current drive (LHCD) with modest powers ( 10% of the total power input) has been used for the first time to completely stabilize performance limiting neoclassical tearing modes in many COMPASS-D tokamak discharges. The stabilizing effect in these experiments is consistent with a reduction in the free energy available in the current pro…

Published
2011

Major developments on MAST have enabled important advances in support of ITER and the physics basis of a spherical tokamak (ST) based component test facility (CTF), as well as providing new insight into underlying tokamak physics. For example, L-H transition studies benefit from high spatial and temporal resolution measurements of pedestal profile …

Published