A new International Atomic Energy Agency (IAEA) coordinated research project (CRP) aims to improve testing of nuclear fuels and structural materials in research reactors, as countries deploy new nuclear reactor technologies, introduce new fuel designs and seek to extend NPP operating life. Before new fuels or structural materials can be used in nuclear reactors, they must be tested and qualified to ensure they meet the most demanding conditions found in nuclear systems.
Research reactors provide a dedicated environment for this work, allowing scientists and engineers to expose materials to radiation, high temperatures and other extreme conditions to understand how they will perform over time.
According to IAEA, demand for irradiation testing is increasing worldwide as interest grows in advanced nuclear systems, small modular reactors (SMRs), fusion technologies, the long-term operation of existing nuclear power plants and high-performance fuels for research reactors. The challenge is not only to conduct more tests, but to maximise the value of each experiment.
To help address this need, the IAEA is launching a four-year CRP to optimise the design of experiments for fuels and materials testing in research reactors. The project will bring together experts from research reactor facilities and stakeholders in fuels and materials testing around the world to improve how irradiation experiments are designed and carried out.
Research reactors have supported fuels and materials testing for decades. There are currently 228 reported operational research reactors worldwide, with 65 engaged in activities in fuel and materials testing, and at least 14 new reactors planned or under construction to serve similar purposes. Irradiation testing in these reactors is central for qualifying new fuels and materials and ensuring safety and performance.
Current methods may be limited in turnaround time, standardisation, and instrumentation, potentially impeding progress for stakeholders. The project seeks to improve throughput and fidelity and adapt to evolving requirements for newer fuels and materials, through information sharing, new testing devices developments, and establishment of a methodology for the design of experiments – thereby enhancing the efficiency and value of each experiment.
Modern fuel and material concepts often require increasingly complex testing conditions, including specific ranges of temperature, pressure, chemistry, neutron fluxes and spectra. Designing devices to reproduce these conditions can be challenging and resource intensive, particularly where irradiation positions are limited.
Many experiments are designed using approaches drawn from local experience or historical practice. While these methods have often been successful, more systematic approaches can improve the quality and comparability of results across facilities. The new CRP will identify good practices, improve methodologies and provide practical guidance for experiment designers.
The project will examine irradiation devices such as capsules, rigs and loops, as well as technologies for monitoring and controlling testing conditions during irradiation. Researchers will also explore advances in instrumentation that enable measurements during irradiation rather than only testing it has been completed.
“Research reactors have a distinctive role in supporting the safe deployment of new fuels and materials for nuclear energy production. They also support the supply of medical radioisotopes,” said Petr Chakrov, Head of the IAEA’s Research Reactor Section. “By improving the way experiments are designed, we can help countries make the best use of existing testing capabilities, plan new ones and foster innovation across the nuclear sector.”
The project is expected to produce recommendations, technical guidance and practical tools to help countries design safer, more effective and more efficient experiments. The results will support the deployment of new reactor and fuel technologies, support the long-term operation of existing nuclear power plants and strengthen research reactor capabilities worldwide.
The objectives of the project are:
- To advance methodologies for innovation in the design of experiments to test nuclear fuels and materials in research reactors worldwide;
- To assess needs and existing methods and techniques for irradiation testing of nuclear fuels and materials in research reactors and identify opportunities for improvement;
- To improve existing and/or develop new methods and techniques for irradiation testing of fuels and materials, including innovative designs for irradiation devices such as capsules, rigs and loops;
- To improve existing and/or develop new methods and techniques for the control and monitoring of irradiation conditions and for in-situ measurements; and
- To develop technical guidance to support the design of experiments for fuel and material testing in research reactors.
The CRP will evaluate and improve existing irradiation methods and techniques, identify opportunities for greater flexibility and responsiveness, and support the development of new irradiation devices and measurement and control tools. Planned outputs include recommendations for experiment design, updated methodologies for irradiation testing, and enhanced infrastructure to meet increasingly complex demands from research communities, industry, and regulatory bodies.
