Challenge Area: Materials for Fusion

Since the 2021 publication of the first UK Fusion Materials Roadmap, in partnership with the UK Atomic Energy Authority (UKAEA), there have been significant advances in fusion materials development, and substantial progress made in UK and global fusion programmes. However, the field is wide, and as power plant programmes explore engineering subsystems in more depth, definition of the materials needs improves and expands.

This important collaborative effort:

• Identifies the facilities, skills, and capabilities required to tackle key challenges
• Highlights cross-cutting themes common to multiple areas of research
• Showcases how solutions can be accelerated through national user facilities and collaborative research

A key takeaway is that many of these challenges have direct synergies with fission, space, defence, medical isotope production and beyond – offering opportunities for greater cross-sector collaboration.

Since the roadmap’s completion in April 2025, fusion has continued to accelerate, most notably with the UK government’s record £2.5 billion investment into UK fusion energy over the next five years, including the design and build of a prototype plant in Nottinghamshire.

Researchers, industry partners, and innovators from across all sectors are invited to engage with this roadmap and help build the foundation for clean, sustainable fusion energy.

The UK Fusion Materials Roadmap, published by UKAEA and Royce, and developed with the input from the UK research community and industry, highlights the key research areas and cross-cutting themes to make commercial fusion a reality.

Fusion – the same principle by which the sun creates heat and light – has the potential to be an abundant, low-carbon and safe part of the world’s future sustainable energy supply.

Recent advances in the technology mean that prototype fusion power stations are now being designed, with the UK’s STEP plant – using the leading ‘tokamak’ design – due to go online in the early 2040s. In 2022, the Secretary of State selected the site of the decommissioned West Burton power station as the location for STEP and in September 2024 UK Industrial Fusion Solutions Ltd. (UKIFS), a wholly owned subsidiary of the UKAEA Group, was established to lead delivery of the STEP programme.

Presently, no facility exists anywhere in the world that fully mimics the fusion environment. The development and qualification of fusion materials can therefore not follow traditional routes. Instead, the fusion materials communities currently utilise existing irradiation facilities to mimic certain aspects of the fusion environment and are developing computational methods to extrapolate and predict material behaviour under fusion conditions.

Five main research areas were identified, with a further four cross-cutting challenges identified, which impacted all research areas. All are addressed in detail within this updated roadmap.

Research Areas

• Magnets and Shielding
• Tritium Breeding: production; anti-permeation barriers; and corrosion resistant coatings
• High Temperature Materials: plasma facing and structural materials
• Radiation Hardened (Rad Hard) Materials
• Modelling and Simulation

Cross-Cutting Challenges

• Regulation, codes and standards, assurance and qualification
• People: skills, training, and developing UK capabilities
• Waste management
• Supply chain

The UK alone cannot solve all fusion materials challenges identified; international collaborations that enable knowledge exchange and unique facility access are vital for achieving global fusion energy. It is hoped that our international colleagues will see this roadmap as an invitation to continue existing and initiate new collaborations with the UK, to work together to solve one of the greatest challenges of our time.

Throughout 2024 and early 2025, a collaboration of over 100 fusion experts from across UK industry, academia and national labs, with support from an editorial board, identified the key materials-related challenges, that need to be solved for the UK to achieve commercial fusion, as well as the supporting skills, infrastructure and capabilities required.