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State-Of-The-Art Report on Structural Materials Modelling Nuclear Science NEA/NSC/R(2016)5 May 2017 www.oecd-nea.org State-of-the-art Report on Structural Materials Modelling State-of-the-art Report on Structural Materials Modelling ORGANISATION FOR ECONOMIC CO-OPERATION AND DEVELOPMENT The OECD is a unique forum where the governments of 35 democracies work together to address the economic, social and environmental challenges of globalisation. The OECD is also at the forefront of efforts to understand and to help governments respond to new developments and concerns, such as corporate governance, the information economy and the challenges of an ageing population. The Organisation provides a setting where governments can compare policy experiences, seek answers to common problems, identify good practice and work to co-ordinate domestic and international policies. The OECD member countries are: Australia, Austria, Belgium, Canada, Chile, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Israel, Italy, Japan, Korea, Latvia, Luxembourg, Mexico, the Netherlands, New Zealand, Norway, Poland, Portugal, the Slovak Republic, Slovenia, Spain, Sweden, Switzerland, Turkey, the United Kingdom and the United States. The European Commission takes part in the work of the OECD. OECD Publishing disseminates widely the results of the Organisation’s statistics gathering and research on economic, social and environmental issues, as well as the conventions, guidelines and standards agreed by its members. NUCLEAR ENERGY AGENCY The OECD Nuclear Energy Agency (NEA) was established on 1 February 1958. Current NEA membership consists of 31 countries: Australia, Austria, Belgium, Canada, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Japan, Korea, Luxembourg, Mexico, the Netherlands, Norway, Poland, Portugal, Russia, the Slovak Republic, Slovenia, Spain, Sweden, Switzerland, Turkey, the United Kingdom and the United States. The European Commission also takes part in the work of the Agency. The mission of the NEA is: – to assist its member countries in maintaining and further developing, through international co-operation, the scientific, technological and legal bases required for a safe, environmentally friendly and economical use of nuclear energy for peaceful purposes; – to provide authoritative assessments and to forge common understandings on key issues, as input to government decisions on nuclear energy policy and to broader OECD policy analyses in areas such as energy and sustainable development. Specific areas of competence of the NEA include the safety and regulation of nuclear activities, radioactive waste management, radiological protection, nuclear science, economic and technical analyses of the nuclear fuel cycle, nuclear law and liability, and public information. The NEA Data Bank provides nuclear data and computer program services for participating countries. This document, as well as any data and map included herein, are without prejudice to the status of or sovereignty over any territory, to the delimitation of international frontiers and boundaries and to the name of any territory, city or area. Corrigenda to OECD publications may be found online at: www.oecd.org/publishing/corrigenda. © OECD 2017 You can copy, download or print OECD content for your own use, and you can include excerpts from OECD publications, databases and multimedia products in your own documents, presentations, blogs, websites and teaching materials, provided that suitable acknowledgment of the OECD as source and copyright owner is given. All requests for public or commercial use and translation rights should be submitted to [email protected]. Requests for permission to photocopy portions of this material for public or commercial use shall be addressed directly to the Copyright Clearance Center (CCC) at [email protected] or the Centre français d'exploitation du droit de copie (CFC) [email protected]. NEA/NSC/R(2016)5 Foreword The Working Party on Multi-scale Modelling of Fuels and Structural Materials for Nuclear Systems (WPMM) has been established, under the auspices of the NEA Nuclear Science Committee (NSC), to review multi-scale models and simulations as validated predictive tools for fuels and structural materials needed in the design of nuclear systems, for fuel fabrication and for understanding performance. The WPMM’s objective is to promote the exchange of information on theoretical and computational methods, experimental validation, and other topics related to modelling and simulation of nuclear materials. The Expert Group on Structural Materials Modelling was established in 2009 to provide targeted critical reference reviews of the state-of-the-art concerning the use of multi-scale modelling to describe the changes induced by irradiation in structural nuclear materials. This expert group aims at reliably reproducing experimental data, while providing keys to understand and interpret existing experimental results, with a view to predicting the behaviour of structural nuclear materials under unexplored conditions and to support the choice and the development of new materials. The topic of the present volume is the development of physical multi-scale models, with their root in computational physics, to describe the changes produced in steels by neutron irradiation. This is performed to underpin structural integrity and lifetime assessments of nuclear power plant components, namely current nuclear reactor vessel and core structural materials internals. 3 NEA/NSC/R(2016)5 Acknowledgements The NEA wishes to express its sincere gratitude to Professor Roger Smith (United Kingdom) and Dr Lorenzo Malerba (Belgium), who co-ordinated this report, to the members of the Expert Group on Structural Materials Modelling and to the authors for their contribution to this report. Special thanks are also due to Dr Par Olsson (Sweden), Chair of the Expert Group on Structural Materials Modelling, and to Professor Dr Theodore M. Besmann (United States) and Dr Marius Stan (United States), current and former Chairs of the Working Party on Multi-scale Modelling of Fuels and Structural Materials for Nuclear Systems. NEA editorial and publishing support was provided by Dr Simone Massara and Ms Reka Tarsi. 4 NEA/NSC/R(2016)5 List of authors R. Smith (Loughborough University, United Kingdom) Editor L. Malerba (Centre d’Étude de l’Énergie Nucléaire - SCKCEN, Belgium) Editor D.J.Bacon (University of Liverpool, United Kingdom) C. Becquart (École Nationale Supérieure de Chimie de Lille - ENSCL, France) V.A. Borodin (Kurchatov Institute, Russia) M.J. Caturla (Universidad de Alicante, Spain) T. Couvant (Électricité de France - EDF, France) A. Herbelin (Électricité de France - EDF, France) Y. Kaji (Japan Atomic Energy Agency - JAEA, Japan) M. Nastar (Commissariat à l’énergie atomique et aux énergies alternatives - CEA, France) K. Nordlund (University of Helsinki, Finland) S.R. Ortner (National Nuclear Laboratory - NNL, United Kingdom) Y.N. Osetsky (Oak Ridge National Laboratory - ORNL, United States) C. Pokor (Électricité de France - EDF, France) N. Sakaguchi (Hokkaido University, Japan) F. Soisson (Commissariat à l’énergie atomique et aux énergies alternatives - CEA, France) R.E. Stoller (Oak Ridge National Laboratory - ORNL, United States) M. Yamaguchi (Japan Atomic Energy Agency - JAEA, Japan) 5 NEA/NSC/R(2016)5 List of abbreviations and acronyms AISI/SAE American Iron and Steel Institute/Society of Automotive Engineers AKMC Atomistic Kinetic Monte Carlo ASTM American Section of the International Association for Testing Materials BBC Body-centred cubic BKL Bortz, Kalos and Lebowitz BWR Boiling Water Reactor CANDU CANadian Deuterium Uranium DBT Ductile-to-brittle transition DBTT Ductile-to-brittle transition temperature DD Dislocation Dynamics DFT Density Functional Theory EAM Embedded-Atom-Method ECP Electrochemical (or corrosion) Potential EKMC Event Kinetic Monte Carlo EGSMM NEA Expert Group on Structural Materials Modelling FCC Face-centred cubic FEM Finite Element Method FP Frenkel pairs GB Grain boundaries IASCC Irradiation assisted stress corrosion cracking IGSCC Intergranular stress-corrosion cracking 6 NEA/NSC/R(2016)5 KMC Kinetic Monte Carlo LWR Light Water Reactor MD Molecular Dynamics MD Matrix damage MTR Materials Test Reactor NDE Non-destructive examination NRT Norgett, Robinson, and Torrens ODS Oxide dispersion strengthened OKMC Object Kinetic Monte Carlo PAS Positron Annihilation Spectroscopy PKA Primary knock-on atom PWR Pressurised Water Reactor RCS Replacement collision sequences RIH Radiation-induced hardening RIS Radiation-induced segregation RPV Reactor Pressure Vessel SANS Small Angle Neutron Scattering SCC Stress corrosion cracking SFE Stacking fault energy SIA Self-interstitial atom SIPA Stress-induced preferential absorption SIPN Stress-induced preferential nucleation SRIM Stopping and Range of Ions in Matter SRO Short range order TEM Transmission electron microscopy 7 NEA/NSC/R(2016)5 TIP Thermodynamics of irreversible processes UTS Ultimate Tensile Strength WPMM NEA Working Party on Multi-scale Modelling of Fuels and Structural Materials for Nuclear Systems WS Wigner-Seitz WWER Water-Water Energy Reactor 8 NEA/NSC/R(2016)5 Table of contents Executive summary ...................................................................................................................................... 10 Chapter 1. Introduction on steels used as structural materials in current nuclear power plants and related modelling issues
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