NEA Mandates and Structures

Expert Group on Structural Materials (EGSM)

Mandate (Document reference):

• The Proposal for Restructuring of the NSC Working Party on Multi-scale Modelling of Fuels and Structural Materials for Nuclear Systems (WPMM), 17 September 2020, [NEA/NSC/WPMM/DOC(2020)2]
• Mandate of the Working Party on Materials Science Issues in Nuclear Fuels and Structural Materials (WPFM) [NEA/SEN/NSC(2021)2]
• Summary Record of the 2^nd meeting of the Working Party on Materials Science Issues in Nuclear Fuels and Structural Materials (WPFM) on May 2022 [forthcoming]
• Mandate of the Expert Group on Structural Materials (EGSM) [NEA/NSC/WPFM(2022)1]

Mandate (Document extract):

Extract from document [NEA/NSC/WPFM(2022)1]

Background

At the invitation of the NEA Steering Committee to all NEA standing technical committees, the Nuclear Science Committee (NSC) launched a prioritisation exercise in 2020. As part of this process, the NSC mandate was revised and NSC activities were prioritised and restructured in order to improve efficiency and maintain the high standard of NSC deliverables, while addressing activities according to the priorities indicated by the member countries. As a result of the prioritisation effort, NSC activities were reformed under the guidance of the NSC Bureau. This has resulted in the consolidation of additional fuel and structural materials activities into the Working Party on Materials Science Issues in Nuclear Fuels and Structural Materials (WPFM). Under the WPFM, two new bodies will cover materials science aspects, one related to nuclear fuel (Expert Group on Fuel Materials or “EGFM”), and one related to structural materials (Expert Group on Structural Materials or “EGSM”).

Scope

Under the guidance of the NSC and the mandate of the WPFM, the EGSM is concerned with the task of conducting joint and comparative studies to:

• Improve the understanding and modelling of the behaviour of structural materials under extreme conditions (such as high temperature, high dose rate and corrosive chemical environment) and for long service lifetime; and

• Support the development, selection and characterisation of innovative structural materials with enhanced performances compared to currently deployed materials.

The EGSM will aim to develop/evaluate experimental methods and data assessment and preservation, together with the advancement of multi-scale modelling and simulation, with a focus on their mutual support to progress validated predictive methodologies for assessment and/or design purposes.

The structural materials that will be considered under the scope of the EGSM may comprise, but are not limited to:

• Metallic structural materials currently deployed in the nuclear fleet;
• Structural materials envisaged for future fission or fusion reactors;
• Advanced materials in terms of chemical composition and microstructure, developed to have unique properties (the development of such materials may be achieved through integrated computational materials engineering);
• Materials or material structures elaborated by novel pathways (i.e. fabrication routes such as additive manufacturing and/or joining processes) applied to existing or new structural materials; and
• Advanced materials in terms of design and architecture (e.g. functionally graded materials), including coated systems.  Some examples of systems could be thin films or coatings deposited by processes such as physical vapour deposition (PVD), high-power impulse magnetron sputtering (HiPIMS), laser processes, and cold spray.

Objectives

The EGSM will develop and maintain international cooperation between member countries on a range of scientific and engineering subjects, such as the following:

• Multi-scale modelling and simulation of structural materials for nuclear systems to investigate their response to extreme operating conditions. Support of the development and implementation of advanced computational techniques for scale bridging and model integration spanning from physics-based computation to data driven modelling;
• Verification and validation of simulations and model predictions through uncertainty analysis, evaluation of approximations, benchmarking of material behaviour simulation tools, and comparison with analytical solutions, as well as experimental data;
• Enhancement of the exploitation of systematic nuclear materials experimental characterisation through the establishment of protocols of execution, data collection and data analysis;
• Engagement with experimental campaigns, such as those performed within the NEA Framework for Irradiation Experiments (FIDES-II), to optimise the link between the irradiation experimental data generated and the needs of the modelling and simulation community;
• Acceleration of nuclear materials discovery by integrating combinatorial fabrication processes, high throughput characterisation techniques, materials modelling and data analysis including machine learning and artificial intelligence;
• Assessment of the current status and future needs for qualification of structural materials;
• Identification of technology readiness level of materials selected for deployment;
• Identification of existing databases and common activities aimed at developing best practices for data formatting and preservation;
• Support for the creation of relevant task forces to address specific technical issues; and
• Organisation of workshops related to structural materials for nuclear energy.

Working methods

The EGSM is a forum for discussion and information exchange. By promoting joint activities at the international level, it fosters collaboration among experts involved in the experimental and computational studies by doing the following:

• Creating opportunities for exchange of information between material scientists, materials manufacturers, designers (of reactor core, fuel cycle infrastructure, etc.) and utilities through the organisation of meetings (workshops, conferences, webinars). The goal is to create the conditions to tackle nuclear materials challenges through a holistic approach that would integrate materials development, prototyping, fabrication, qualification, licensing and deployment into a consistent perspective. Organisation, as relevant, of opportunities for exchanges with non-nuclear materials development experts to share potentially common practices and approaches;
• Establishing task forces involving leading technical experts to address issues including links between modelling and validation in materials, definition of best practices in the area of the nuclear material microstructural characterisation and microstructural evolution modelling and simulation, and the relationship of microstructure to material properties; and
• Conducting joint and comparative studies to support the development, selection and characterisation of innovative structural materials (new compositions, numerical design) and advanced materials solutions (novel elaboration pathways, coated systems, new designs and architectures, etc.).

The EGSM will report its progress at the annual meeting of the WPFM.

Membership

The EGSM is both a forum for international exchanges between experts and a task-oriented expert group that is composed of a diverse range of specialists in the field of nuclear structural materials. The expert group consists of specialists in multi-scale modelling and simulation of structural materials as well as specialists in experiments at multiple scales that relate to structural materials in nuclear systems.

Interactions

The EGSM will liaise closely with other NSC subsidiary bodies in order to ensure coordination of their respective programmes of work and provide advice and support, where required, and undertake common activities, where appropriate.

For information exchange and mutual support through sharing of expertise and reciprocal advice, the EGSM will liaise with materials science-related NEA joint undertakings such as the Accident Tolerant Fuel cladding bundle testing at QUENCH facility in KIT, Germany (QUENCH-ATF).

The EGSM will exchange information with FIDES-II and support its activities (especially on modelling and simulation of material behaviour under irradiation) as relevant and in compliance with the data dissemination policy. The efforts will include providing advice on the prioritisation of the data needs for the parameterisation and validation of nuclear materials modelling and simulation tools, and expertise on the analysis and interpretation of the experimental data related to the post irradiation examination studies.

The EGSM will liaise closely with other relevant NEA bodies to develop cross-cutting activities and  provide advice and support where required. In particular, collaborations are envisaged with the activities undertaken under the auspices of the Committee on the Safety of Nuclear Installations (CSNI), including the Working Group on Integrity and Ageing of Components and Structures (WGIAGE), and the Studsvik Material Integrity Life Extension (SMILE) joint project. Through the WPFM, EGSM will liaise with the Radioactive Waste Management Committee (RWMC) through the development of its new activities in the domain of the application of materials as a factor of optimisation of radioactive waste management programmes. 

The EGSM will work closely with the NEA Data Bank on database and knowledge preservation activities.

The EGSM will collaborate with industry representatives, as relevant, and international organisations such as the International Atomic Energy Agency (IAEA), the European Commission (EC) and the Generation IV International Forum (GIF).

Deliverables

The EGSM will publish reports and journal articles stemming from EGSM activities. The activities will cover the following topic areas:

• State-of-the-art assessment of specific areas to be considered as priorities for research;
• Experimental and numerical protocols and standards, and facilitating the sharing of available experimental installations and simulation frameworks; and
• Development of common databases.

Specifically, the EGSM will:

• Support the European Database for Multiscale Modelling of Radiation Damage (ENTENTE) programme in the data models development through establishing frameworks for discussions between the ENTENTE participants and other international research organisations to share experiences, best practices and pursue international consensus on data curation and preservation strategies;
• Publish a report on recommendations on Cladding materials properties for fuel performance codes to exploit the work performed by the EGIFE on material properties;
• Publish the Executive Summary of the Structural Materials for Innovative Nuclear Systems (SMINS-6) workshop;  
• Revitalise the activity on defining protocols, standards and best practices in characterisation of nuclear materials;
• Publish the executive summary of the 2021 Workshop on High-Entropy Alloys, remotely organised in cooperation with CIEMAT on October 19 to 21, 2021 by the former Expert Group on Innovative Structural Materials; and
• Investigate the possibility of launching an international collaboration focusing on complex concentrated alloys.