Oxford Sigma is pleased to announce the publication of its latest peer‑reviewed paper, “Qualification Pathways for Fusion Structural Materials,” in the Journal of Nuclear Engineering Special Issue Fusion Materials with a Focus on Industrial Scale‑Up. The Special Issue has been edited by Prof. Dr. Jan Willem Coenen alongside Dr Thomas P. Davis, Oxford Sigma’s CEO and Chair of ASME BPVC Section III Division 4, marking the company’s continued leadership in shaping fusion engineering standards. The publication reinforces Oxford Sigma’s position at the forefront of establishing engineering evidence and codified rules for future fusion systems.
Good engineering starts with evidence. In fusion, that means demonstrating how a material behaves under neutron (fuel type dependent) irradiation, thermal, mechanical, and chemical conditions, not relying on assumptions or idealised properties. This is the purpose of qualification: a structured, engineering‑led process that establishes confidence that a material or component will perform its intended function in its intended environment.
Qualification is frequently mistaken for codification, but the two are fundamentally different. Codification places a material into a design code. Qualification generates the evidence that makes codification, and safe operation, possible (component dependent). Because fusion environments vary between designs, only the owner or designer can determine what evidence is needed. This paper provides a clear, graded framework that shows how to build that evidence chain and how early qualification accelerates the path to codification and deployment.
Importantly, the paper makes clear that qualification does not need to be fully complete before a fusion facility begins operation. Fusion programmes can adopt a phased approach, where early, time‑limited operation proceeds under controlled conditions while further evidence is generated. The level of qualification required before first plasma depends on the owner’s risk tolerance, the functional role of the component, and the degree of uncertainty reduction the owner judges acceptable. This graded approach enables progress while still building the datasets needed for long‑term justification and eventual codification.
A central message of the paper is that qualification, not just nominal material properties, determines how quickly fusion systems can be built, justified, and licensed. Using detailed case studies of Eurofer97 and SiCᶠ/SiC composites, the paper explains why qualification evidence gaps, not theoretical performance, are the rate‑limiting step for deployment.
- Eurofer97, although relatively mature, still requires key evidence such as irradiated creep behaviour, weld performance under representative conditions, and environmental compatibility datasets.
- SiCᶠ/SiC composites offer exceptional high‑temperature and low‑activation behaviour but require advances in joining technologies, irradiation testing, and the adoption of probabilistic design approaches appropriate for brittle composite systems.
These comparisons illustrate why tailored, component‑specific qualification pathways are essential before materials can be codified for pressure‑boundary use.
The full scientific paper is available through the Journal of Nuclear Engineering Special Issue Fusion Materials with a Focus on Industrial Scale‑Up, cited as:
Lewis, E.R.; Anderson, G.; Martinez de Luca, D.; Young, B.A.; Davis, T.P. Qualification Pathways for Fusion Structural Materials. J. Nucl. Eng. 2026, 7, 23. https://doi.org/10.3390/jne7010023
“Qualification is not about having complete knowledge before first operation; it’s about reducing uncertainty to a level the owner considers acceptable. Early, limited operation can generate essential evidence, and codification follows only when that evidence is mature. This graded, risk‑informed approach is what will allow fusion technologies to advance at pace.”
~ Dr Thomas P Davis, Co-Founder and CEO, Oxford Sigma
“It’s vital that we keep fusion anchored in engineering reality. Commercialisation will only accelerate if first‑of‑a‑kind devices are built using qualified, well‑understood materials, not ‘unobtanium’, but dependable systems we know how to justify and inspect. Proof‑of‑concept must come first, and using reliable materials is the surest route to delivering safe, trustworthy, power‑generating fusion plants.”
~ Dr Emily Rose Lewis, Nuclear Materials Engineer, Oxford Sigma
About Oxford Sigma
Oxford Sigma is a Fusion Technology company with a vision to tackle energy security and climate change by accelerating the commercialisation of fusion energy. Our mission is to deliver materials technology, materials solutions, and fusion design services. Oxford Sigma aims to produce advanced materials technologies, agnostic to fusion approach, for the materials ecosystem. Our fusion core materials are engineered to enable longer term operations for fusion pilot plants, with the aim of roll out to the first-of-a-kind commercial power stations. Oxford Sigma is internationally recognised as a key fusion materials and technological leader.
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