Surrey to evaluate weld integrity of fusion plant steel

Materials engineers at Surrey University are gathering data and developing a simulation model to prove whether welds are safe and effective to use in future fusion energy plants.

The Surrey University research team (L-R): Dr Mark Whiting, Bin Zhu, Dr Tan Sui (Image: Surrey University)

The Surrey research team said it will use its expertise to upgrade stress measurement techniques that can allow scientists to map the residual pressure within a volume of steel, rather than in single points. The work is being carried out in an international collaboration with partners that include the UK Atomic Energy Authority’s fusion research centre in Culham, and STFC’s ISIS Neutron and Muon Source.

In a statement, research leader Dr Tan Sui, senior lecturer in Materials Engineering at Surrey University, said: “Developing techniques and introducing new approaches to UK research is essential if we’re to move towards energy generated through fusion, which could be a key part of the world’s long-term energy needs by the second half of this century.

"Our next step is to process the data acquired through these processes into a simulation model which will enable us to accurately predict the residual stress on EUROFER 97 steel joints after welding.”

EUROFER 97 steel has been developed as a structural material candidate for components of future fusion powerplants. It will need to withstand temperatures of 550°C and high levels of irradiation without degrading. The Surrey team is focusing on investigating the integrity and longevity of the steel welds, which would be required in the construction of the fusion reaction chamber.

Dr Yiqiang Wang, senior materials engineer at the UK Atomic Energy Authority, said: ‘‘We are now entering the engineering design phase for the next generation of nuclear fusion power plants, building upon decades of research at UKAEA and the wider international fusion community. Our team will tackle engineering challenges to accelerate fusion demonstrators.

“This collaboration between Surrey University, UKAEA, EUROfusion, the Science and Technology Facilities Council’s ISIS Neutron and Muon Source and industry will continue to demonstrate the efficiencies offered by cross-sector and international partnerships in accelerating the development of fusion energy technologies.”

The Surrey team’s research exploring residual stress distribution in laser welded Eurofer97 steel has been published in the Journal of Materials Science & Technology.