Irradiated Superconductors in High Magnetic Fields for Compact Fusion Energy Tokamaks (Experimental PhD – Materials Strand project).

Supervisor/s – Professor Damian Hampshire (Durham University) and Dr F Schoofs (CCFE)

Background to the Research Project:

CCFE will soon install (scheduled for December 2019) a state-of-the-art 14 Tesla cryogenic physical properties measurement system (PPMS) in the MRF facility, for (inter alia) measuring the superconducting properties of irradiated superconductors in high magnetic fields. The PPMS provides the opportunity for staff at CCFE and at Durham to collaborate making transport, magnetic and thermal measurements in high magnetic fields on irradiated superconducting materials for compact tokamak fusion energy applications. This facility is unique in the UK. We intend to understand and control the properties of irradiated low and high temperature superconductors with a view to optimising their use in the design and operation of the TF and PF coils in compact tokamaks.

At the beginning of the 21st century, the ITER (International Thermonuclear Experimental Reactor) Tokamak that is being built in Cadarache in France is one of the most exciting scientific projects in the world (http://www.iter.org/). It will produce 500 MW which is about ten times the power needed to run the machine.  Superconductivity is the enabling technology for this project since without it, the magnets that hold the plasma would either melt or consume more energy than the tokamak produces. Approximately one third of the cost of ITER comes from the superconducting magnets. After ITER, we expect new tokamaks to be built across the world that will help enable commercial fusion energy.

In ITER, the superconducting magnets are so strongly shielded that the irradiation reaching the superconducting magnets can be neglected. However in the most promising recent prototype commercial fusion designs, the tokamaks are compact and operate at high magnetic fields (e.g. the UK Spherical Tomamak for Energy Production (STEP) or the Commonwealth Fusion Systems (CFS) designs at MIT). The real estate in the central column (typically 50 cm of shielding and 10 cm radius of conductor) of these compact designs is highly irradiated and extremely valuable, because it simultaneously helps determine the irradiated lifetime of the superconductor, the thermal load to the cryogen and the maximum magnetic field of the plasma. In order to optimise the design of the central column, the fusion energy community needs to know the behaviour of state-of-the-art superconductors in high fields during and after irradiation. In this PhD project, colleagues in Durham and at CCFE will collaborate to characterise and understand irradiated superconductors under commercial fusion energy relevant conditions.

PhD Research Project and Supervision:

The superconducting magnets in compact tokamaks such as STEP will see relatively high levels of irradiation. The effects of this irradiation must be measured, understood and accounted for in optimal designs. The PhD research project will be experimental.  It will include a collaboration between Durham University and The Culham Centre for Fusion Energy (CCFE) irradiating, measuring and understanding irradiated superconducting materials. This PhD project is ideal for a student with a good degree in Physics and a broad interest in fusion, materials and applied Physics. This PhD project will consider both traditional low temperature and high temperature superconductors. They will be expected to network with scientists throughout the world working on fusion.

The PhD supervisors are: Prof. Damian Hampshire who is an experienced member of the high-field applied superconductivity and fusion energy community and Dr. Frank Schoofs who is an expert on technological development for fusion power plants. The 4 year PhD is funded through the Fusion CDT partnership which gives an excellent exposure to many of the best Universities in the UK, an excellent taught course in fusion energy and exposure to the fusion community across Europe. The PhD is formally based at Durham for access to high magnetic fields and cryogenic facilities, but the training in the fusion CDT means you spend about 6-8 months during the first year of your PhD at CDT partner Universities and will include regular visits to CCFE. It will also probably involve working in an International laboratory (usually the USA, Japan or EU) for at least one collaborative project in the 2nd or 3rd year. The Research Groups are committed to developing an environment that produces world-class science and is inclusive, flexible and family-friendly.

References: (i) P.O. Branch, Y. Tsui, K. Osamura and D. P. Hampshire. Weakly-Emergent Strain-Dependent Properties of High Field Superconductors. Nature Scientific Reports 9:13998 (2019).  (ii) United Kingdom Patent Application No. 1707392.5   Inventors:  T Lee, E Surrey and D P Hampshire. Applicant: University of Durham. Title :  Superconducting Magnet. Date Lodged with IPO: 11 May 2017  (iii) Yeekin Tsui, Elizabeth Surrey and Damian Hampshire. Soldered Joints – An essential component of demountable HTS fusion magnets – SUST 29 075005 (2016)  – Highlights of 2016 :  SuST Highlights of 2016

The project will be mainly based in Durham University, but will include regular visits to CCFE. It will involve overseas travel to: Japan or the US for a collaboratory for 6 – 8 weeks; the USA and/or Japan and/or Europe for conferences and collaborations; Japan or France to use International High Field Facilities.

Skills the student will learn during the PhD:
i) Transferable Skills:

  • Communication: Presentations at conferences and developing collaboration.
  • Personnel: Networking skills. Working with expert senior staff, junior staff and staff providing services.
  • Writing: Reports, Conference and Journal publications.
  • Computerised Data Acquisition and Analysis.
  • Technical Design: CAD Design of hardware with new functionality and understanding materials
  • Knowledge: Understanding magnetically confined fusion and high field superconductors.
    Time management.

ii) Specialist Skills and Know-how.

  • Knowledge: High field superconductors for fusion applications.
  • Use of: High magnetic fields; Cryogenic liquids; Irradiated samples; materials at high and at cryogenic temperatures.
  • Design of new experiments.

This project is offered by Durham University. For further information, please contact Prof. Damian Hampshire at: d.p.hampshire@durham.ac.uk – send your CV, a covering e-mail that includes a brief explanation of why you are interested in Superconductivity and Fusion Energy and your availability for interview. Web-pages:  http://www.ccfe.ac.uk/JET.aspx and http://community.dur.ac.uk/superconductivity.durham/personnel.html.

CCFE is the fusion research arm of UKAEA.