Investigating the Influence of Residual Elements on the Mechanical and Microstructural Performance of Reduced activation ferritic/martensitic (RAFM) steels in Fusion Reactors

About the Project

The Nationally Determined Contribution (NDC) under the Paris Agreement aims to reduce CO₂ emissions by 68% from 1990 levels by 2030, with particular emphasis on high-impact sectors such as industry and transportation, especially the steel industry. The iron and steel sector is one of the most energy-intensive industries and a major contributor to greenhouse gas emissions, accounting for approximately 8% of global CO₂ emissions and nearly half of all emissions from material production.

Research has shown that using steel scrap instead of virgin iron ore in steelmaking can reduce CO₂ emissions by up to 58% and water consumption by 40%, while conserving critical natural resources such as coal and iron ore. The electric arc furnace (EAF) route, which allows for up to 100% scrap recycling, offers a sustainable pathway for low-carbon steel production. As electricity generation increasingly shifts to renewable energy sources, CO₂ emissions from EAF-based steelmaking could approach near-zero levels.

Recognizing these advantages, the UK has prioritized the transition to EAF-based steel production as part of its decarbonization strategy. To achieve sustainable steel recycling without dilution, it is crucial to understand how residual elements influence the microstructure and mechanical properties of steels. This challenge becomes even more complex under demanding service conditions, such as those encountered in fusion reactors. Reduced Activation Ferritic-Martensitic (RAFM) steels have been developed as primary structural materials for the first wall and blanket components in fusion systems, including the International Thermonuclear Experimental Reactor (ITER) and Spherical Tokamak for Energy Production (STEP) program.

The extreme operating conditions in fusion environments, characterized by intense neutron irradiation, temperatures exceeding 650 °C, and high magnetic fields (>10 T), impose significant stresses on structural components. These include magnetic, pressure, and thermal stresses that can exacerbate the detrimental effects of residual elements. Such elements tend to segregate at grain boundaries and at precipitate–matrix interfaces, leading to embrittlement and degradation of mechanical properties. For example, sulfur and phosphorus can form low-melting eutectics that promote crack initiation during thermal cycling, while elevated levels of Cu, Mn, Si, Ni, and Mo can increase the risk of cracking during cooling.

The objective of this PhD project is to develop experimental methods that realistically simulate operational conditions in order to investigate the effects of residual elements on the microstructure and mechanical properties of RAFM steels. To achieve this, the project will utilize state-of-the-art microstructural characterization facilities at the University of Manchester and within the Royce Institute. Techniques such as in-situ EBSD and TEM with heating holders will be employed to replicate high-temperature service environments, while heavy-ion irradiation will serve as a surrogate for neutron damage, complemented by controlled helium implantations.

This PhD project will therefore focus on understanding how residual elements influence the microstructural evolution and mechanical performance of RAFM steels under irradiation and high-temperature conditions. The resulting insights into the role of residual elements will help establish guidelines for tolerating higher impurity levels, promoting the use of recycled steel scrap, and ultimately reducing the carbon footprint and energy demand of steelmaking. These findings will also provide valuable principles for designing next-generation, highly processable RAFM steels. Ultimately, this research aims to reinforce the UK’s position as a global leader in fusion reactor materials development.

Applicants should have, or expect to achieve, at least a 2.1 honours degree or a master’s (or international equivalent) in a relevant science or engineering related discipline.

Funding

This is a 3.5-year PhD. Excellent candidates will be nominated for faculty funding (application deadline for faculty funding is 19th December 2025. If no suitable applications are received in December, a further round of applications will be considered for the deadline 13th March 2026).

For more information, visit our funding page or search our funding database for specific scholarships, studentships and awards you may be eligible for.

We recommend that you apply early as the advert may be removed before the deadline.

Before you apply

We strongly recommend that you contact the supervisors for this project before you apply. Please include details of your current level of study, academic background and any relevant experience and include a paragraph about your motivation to study this PhD project.

Please email to Peng Gong: peng.gong@manchester.ac.uk

How to apply

Apply online through our website: https://uom.link/pgr-apply-2425

When applying, you’ll need to specify the full name of this project, the name of your supervisor, if you already having funding or if you wish to be considered for available funding through the university, details of your previous study, and names and contact details of two referees.

Your application will not be processed without all of the required documents submitted at the time of application, and we cannot accept responsibility for late or missed deadlines. Incomplete applications will not be considered.

After you have applied you will be asked to upload the following supporting documents:

• Final Transcript and certificates of all awarded university level qualifications
• Interim Transcript of any university level qualifications in progress
• CV
• Supporting statement: A one or two page statement outlining your motivation to pursue postgraduate research and why you want to undertake postgraduate research at Manchester, any relevant research or work experience, the key findings of your previous research experience, and techniques and skills you’ve developed. (This is mandatory for all applicants and the application will be put on hold without it).
• Contact details for two referees (please make sure that the contact email you provide is an official university/work email address as we may need to verify the reference)
• English Language certificate (if applicable)

If you have any questions about making an application, please contact our admissions team by emailing FSE.doctoralacademy.admissions@manchester.ac.uk.