Development of Automated Robotic W Machining for In-Vessel Component Repair in Fusion (C3.5-MAC-Ghadbeigi)

W (Tungsten) is expected to be used extensively within fusion reactors for in-vessel, plasma-facing, armour components due to favourable material properties such as a high melting point, low sputtering, and low Tritium uptake. However, during reactor D-T operations, the plasma facing components may be damaged by either erosion resulting from exposure to long plasma discharges (long term) or transient events (i.e., runaway electrons). Therefore, it is also expected that large amounts of the W components will need to be repaired, in-situ or ex-situ, for reuse. Besides, initial manufacturing of the W components is also challenging, for example in machining due to it being particularly hard and brittle – leading to very high tool wear, and difficulty in making accurate features.

It is possible to machine W using standard machining devices, such as on a CNC machine, together with the appropriate machining strategy – however these are large, immobile pieces of equipment. The W components may be in different shapes, thicknesses, as well as positioned in various locations with limited access and orientations that together with their very poor machinability makes in/out of vessel repairs very challenging task. In-vessel repairs would therefore need to take into consideration these complications, and the cramped, hazardous environment, and use only sufficiently miniaturised tools and end effectors on robotic arms – introducing much more complex machining dynamics problems. Serial kinematic robot arms, for example, can suffer from severe self-excited vibrations during machining.

The project is part funded by UKAEA and RACE in collaboration with Advanced Manufacturing Research Centre, University of Sheffield. 

About the UKAEA and RACE:

As the UK’s national fusion lab, the UK Atomic Energy Authority (UKAEA)’s mission is to lead the commercial development of fusion power and related technology, and to position the UK as a leader in sustainable fusion energy.

The UKAEA has until recently operated the JET tokamak on behalf of European partners, and is now starting to decommission the device. UKAEA also operates the UK’s own MAST Upgrade fusion experiment and leads the STEP (Spherical Tokamak for Energy Production) programme, which aims to design and build a demonstration fusion powerplant by the early 2040s. RACE is a business unit of UKAEA, specifically focussing on developing remote and robotic systems to carry out tasks in hazardous and extreme environments. For future fusion power plants, this capability is device defining and critical to commercial viability, where remote and robotic operation and inspection over long periods of time is essential. RACE also works with academia and industry on bringing remote maintenance technology into other sectors such as decommissioning and space.

Interested candidates are strongly encouraged to contact the project supervisors to discuss your interest in and suitability for the project prior to submitting your application. 

Please refer to the EPSRC DLA webpage for detailed information about the EPSRC DLA and how to apply.