[en] In this chapter, the multiscale nature of radiation effects in materials is illustrated, and the meaning and role of a multiscale modelling approach explained. The modelling tools used in the SMoRE CRP are then overviewed as classified based on the processes the models deal with, namely atomic level phenomena, nanostructural and microchemical evolution and mechanical behaviour. The range of applications, strengths and weaknesses of each modelling tool is discussed. (author)

[en] The results of radiation simulation experiments on different metals and alloys are presented and analysed in this chapter. Using irradiation with charged particle beams, it is possible to reproduce and examine many of the known radiation effects and investigate the physical nature of these effects, in detail, under well-controlled conditions. Additionally, the characteristics of some radiation sources used for studies of radiation effects and some experimental procedures are presented. Accelerator systems, with accompanying high technology instrumentation and methodologies for analysis of experimental data, are shown to provide a comprehensive tool for the determination of mechanisms of radiation damage and the selection of materials with high radiation resistance. (author)

[en] This SMoRE CRP has used a wide variety of microanalytical tools to extract data from ion beam simulations of neutron damage to reactor structural materials. While some of these tools have been used for many years, others are very new and are undergoing continuous evolution and refinement. These tools have significant advantages but also have unique limitations and disadvantages. This chapter reviews the major techniques and their characteristics, especially those that require reporting significantly more experimental details than might usually be included in general publications. (author)

[en] This chapter reviews the materials issues that prevent the use of austenitic steels as fuel cladding for doses above 100-150 displacements per atom (dpa) and thereby preclude an increase in fuel burnup. The limited neutron data on ferritic and ferritic-martensitic alloys and their oxide dispersion strengthened (ODS) variants is then presented, which shows promise that these alloys can be subjected to much higher exposures, thereby allowing higher fuel burnups. Finally, the results of recent ion irradiations are presented, demonstrating that ion irradiation can be used successfully as a surrogate to explore void swelling at much higher dpa levels, in the range 300-600 dpa. However, there are enough differences in the neutron and ion environments that modelling assistance is required to extrapolate ion results to neutron conditions, especially for the effects of displacement rate and temperature. (author)

[en] This publication summarizes the findings and conclusions of the IAEA coordinated research project (CRP) on accelerator simulation and theoretical modelling of radiation effects, aimed at supporting Member States in the development of advanced radiation resistant structural materials for implementation in innovative nuclear systems. This aim can be achieved through enhancement of both experimental neutron-emulation capabilities of ion accelerators and improvement of the predictive efficiency of theoretical models and computer codes. This dual approach is challenging but necessary, because outputs of accelerator simulation experiments need adequate theoretical interpretation, and theoretical models and codes need high dose experimental data for their verification. Both ion irradiation investigations and computer modelling have been the specific subjects of the CRP, and the results of these studies are presented in this publication which also includes state-of-the-art reviews of four major aspects of the project: challenges and trends of structural materials development for present and future reactor designs, accelerator methodologies for material testing, multiscale modelling tools, and advanced examination techniques.