Dr Jessica Marshall, Dr Gurdev Singh
Research on a variety of radiation dense materials is performed in this group with a focus on the borides and carbides of tungsten. Research themes cover a range of topics from fundamental characterization of radiation response through to processability of radiation dense materials for use as compact radiation shielding.
Materials of interest include Cemented Tungsten Carbides (cWCs) and Reactive Sintered Borides (RSBs).
Radiation studies in silico and experimental work is a critical aspect of this project.
These interests span a wide range of condensed matter physics with a focus on multiscale characterization and structure-property relationships within materials. These include:
Current research themes:
- Thermal analysis of different cWC, RSB and tungsten boride compounds
- Sintering studies for fully dense cWC-RSB materials
- X-ray studies of sintered and oxidized cWC-RSB materials
- Single crystal growth for evaluation and radiation response
- Evaluation of disordered relaxor ferroelectric systems as radiation sensors
These materials have the potential to be a suitable compact radiation shield that can also withstand extreme conditions within a power generating fusion reactor. RSB materials are strategically significant to fusion power due to their high tungsten boron content and that they do not significantly activate under neutron and gamma irradiation.
RSBs are also of interest in that they have the potential to be synthesized as for cWCs but their novelty means that very little data on their mechanical properties and processability exists.
The diagram below shows that material selection for an activating environment is limited by the material's activation potential particularly under neutron irradiation. This results in a limited number of materials that are suitable for consideration and prevents certain common high-temperature alloys such as Ni-based superalloys being used in or near the plasma chamber.
RSB materials are strategically significant to fusion power due to their high tungsten boron content and that they do not significantly activate under neutron and gamma irradiation.
If the cWC-RSB concept is demonstrated as a practical solution for compact spherical tokamaks, this will mark the first application of this concept and a proof of principle prior to other related applications for these materials in future.
Earlier work on Radiation Dense Materials is linked here:
For the lastest news and practical work on the cWC-RSB concept:
Links to posters on Radiation Dense Materials from this group:
(a) PFC surface, (b) Outer cWC shield, (c) Coolant/moderator channel, (d) Expansion from internal void formation, (e) Voids and H/He bubbles, (f) γ-ray generation from absorption (g) Plasma erosion, (h) ions, neutrals and impurities from sputtering, (i) Plasma discharge (~GJ m-2) (j) Molten metal re-deposition and particle formation from (i), (k) RSB inner shield, (l) Vacuum gap between inner shield and cryogenic core, (m) HTS magnets and cryostat, (n) Steel central support column.