The OECD Nuclear Energy Agency (NEA) organised the Third International Workshop on Structural Materials for Innovative Nuclear Systems (SMINS-3). The workshop was held in Idaho Falls, USA on 7-10 October 2013, hosted by the Idaho National Laboratory (INL) and co-sponsored by the European Commission (EC) and the International Atomic Energy Agency (IAEA).

Materials research is a field of growing relevance for innovative nuclear systems, such as Generation IV reactors, critical and sub-critical transmutation systems and fusion devices. For these different systems, structural materials are selected or developed taking into account the specificities of their foreseen operational environment. However, material development projects require both cross-cutting research programmes and advanced experimental/simulation facilities so as to characterise and evaluate the performance of the selected materials.

The purpose of this workshop was to stimulate an exchange of information on current materials research programmes for different innovative nuclear systems with a view to identifying and developing potential synergies.

The workshop covered fundamental studies, modelling and experiments on innovative structural materials including cladding materials for the range of advanced nuclear systems such as thermal/fast systems, sub-critical systems, as well as fusion systems.

Five topics were suggested:

1. Fundamental studies
2. Metal Alloys
3. Ceramic and Ceramic Composites
4. Advanced Materials and Processing/Joining
5. Ion vs. neutron irradiation

Fundamental studies focused on the identification of mechanisms driving the response of materials under the conditions expected in innovative nuclear systems. These mechanisms may have acted at the atomic or higher scale with the application of multiscale approaches, together with related problems of scale-bridging or numerical methods, were of special interest. Moreover, irradiation experiments and subsequent characterization of materials with analytical techniques were included in the session if it aimed at better understanding the acting mechanisms or drawing physics-based correlations.

Metal Alloys, Ceramic and Ceramic Composites included in- and out-of-core applications which took into account the scope of data availability and gaps (considering also licensing issues); experimental and modelling needs for specific components or degradation modes; the link between R&D, standardisation and experimental protocols; coolant effects and mechanical properties. Code development and implementation plans were also discussed. Application of SiC composites to LWR systems was of interest as an advanced concept.

Advanced materials may have included nano-grained materials, grain boundary engineered materials, nano-precipitation-strengthened materials and micro-laminates, processing and joining among other topics.

The Ions vs. neutron irradiation topic focused on specific irradiation comparisons including mechanical properties and microstructural effects caused by ion or neutron irradiation. Comparative irradiation studies on a common material were also welcome.

It is noted that fuel-cladding interaction was not covered in this edition of the workshop.

Plenary lectures on the following subjects were organised:

• Industrial perspectives on material choices for advanced nuclear systems
• Code qualification and material data needs for licensing
• Comparison of ion and neutron irradiation for creating radiation damage
• Use of user facilities for the R&D of innovative materials
• Perspectives on modelling materials far from equilibrium

Technical sessions were organised according to the five topics listed above.

A workshop discussion session on ion vs. neutron irradiation was organized.

A two poster session was held on the second and third day (8-9 October 2013), covering all technical subjects.

Download the proceedings for  Structural Materials for Innovative Nuclear Systems (SMINS-3) Workshop Proceedings (7-10 October 2013).