From left: David Bowden, Materials for Fusion Lead at UKAEA, Yutai Kato, Prof Steve Zinkle, ORNL and University of Tennessee, and Dr Amanda Quadling. Photo: UKAEA
Five year study will examine behaviour of materials for fusion power plants
A $3.6m fusion energy partnership has been launched by the UK Atomic Energy Authority and the US Department of Energy’s Oak Ridge National Laboratory.
In a five-year project, the two organisations will examine the performance and behaviour of materials required for use in future commercial fusion power plants.
The partnership will firstly involve irradiating materials using neutrons at Oak Ridge’s High Flux Isotope Reactor, a science facility in the US.
They will then test these materials at Oak Ridge and at the UKAEA’s Materials Research Facility at Culham Campus in England.
The research has been initiated because one of the major challenges in harnessing fusion energy is developing materials to cope in extreme environments.
This is because high-energy neutrons and extreme temperatures can weaken or change the desirable mechanical, thermal, optical or electronic properties of materials, which can reduce the lifetime of fusion machines.
The research will attempt to understand how certain materials respond to irradiation over extended periods, in order to increase the longevity of the materials used.
Dr Amanda Quadling, UKAEA’s Director of Materials Research, said the partnership “will allow UKAEA access to ORNL’s archive of existing irradiated materials, which include binary iron-chromium alloys, advanced steels, silicon carbide composites and copper alloys.
“Alongside this, UKAEA will also be placing entirely new materials into the ORNL High Flux Isotope Reactor, including new high-temperature steels developed by both UKAEA and wider UK industry, permeation barrier coatings and welded materials.”
Dr Yutai Kato, ORNL’s Interim Director of Materials Science and Technology Division and Manager of Fusion Materials Program, said the materials researched under the partnership “will primarily focus on the ‘breeder blanket’ – a component to provide the fusion fuel, tritium, to make power plants self-sufficient”.
Post irradiation testing will include tensile and hardness property measurements, to understand both the effect and extent of radiation-induced hardening and concurrent loss of ductility in these materials.
Advanced microstructural analysis will also be carried out to understand effects of neutron radiation on chemical segregation and precipitate stability.
These assessments are critical to provide assurance that these alloys will be sufficiently durable and reliable to support a fusion power plant throughout the expected lifetime of each component.
In 2021, UKAEA launched the UK Fusion Materials Roadmap with a view to deliver new neutron resilient materials as well as a suite of irradiation and post-irradiation test work to provide design engineers with data to build future fusion power plants.
The learnings gained from the work will be published in journals and materials handbooks, and shared wider with industry to accelerate the development of new materials for fusion applications.
The partnership will also see staff from the US and UK visit their counterpart facilities via secondments to share industry skills.
