Oxide-dispersion-strengthened Steels for High Temperature Fusion

Supervisors

• Professor Bo Chen
• Dr Christos Skamniotis

Project description

The landscaping report of the UK Fusion Materials Roadmap 2021-2040, has identified a major R&D area, that is to develop the next-generation high-temperature steels with engineering assurance for enabling a fusion power plant. The deuterium-tritium fusion reactor environment represents one of the most demanding environments the engineering materials will face, with the combination of elevated temperatures at or above 650 degrees celcius under loads (e.g. creep and fatigue) and significant neutron irradiation. 

Oxide dispersion strengthened (ODS) steels containing high number density of nano-oxide particles can effectively pin the sub-micron ferritic grains rendering enhanced high-temperature creep performance, and act as sinks/traps for irradiation defects providing excellent resistance to fusion neutron-induced property degradation. However, a major challenge that prevents the wider adoption of ODS steels is the high cost, inhomogeneous microstructure and anisotropic property associated with the powder metallurgy fabrication at the present time. In partnership with the UKAEA (e.g. two industrial supervisors), this PhD project will focus on the process control of ODS steels fabricated by hot isostatic pressing (HIP) to achieve a better microstructure control and high-temperature mechanical performance. The overarching aim is to understand mechanisms and predict densification behaviour and microstructure evolution during HIP process of oxide-dispersion-strengthened (ODS) steels in order to obtain the optimum microstructural and mechanical properties at 650 degrees celcius and above.

The research is ultimately aligned to both the UK and global initiatives addressing two areas of the Engineering Net Zero and Sustainable Manufacturing. The success of the PhD project will contribute to our knowledge about two of the cross-sector materials degradation mechanisms (e.g. creep and fatigue), and help creating technological solutions to decarbonise our economy and society.