1. Materials Ageing – Irradiation Embrittlement

Following a preliminary assessment of the relative importance of the various ageing mechanisms experienced by materials used in European nuclear power plants (NPPs), the primary purpose of this synthesis report is to deliver a coherent and comprehensive review of research into irradiation embrittlement performed during Euratom Research Framework Programmes 4, 5, 6 and 7, linking the research to the related projects, reports, materials and components.

To ensure a consistent treatment of a given ageing mechanism and across different ageing mechanisms, consideration is given to the research outputs from Euratom research projects that meet the following criteria:

• Sufficiently detailed information exists regarding materials and conditions of experiments or simulations;
• The materials in the experiments or simulations correspond to those used in operating European NPPs;
• The conditions investigated correspond to the operating conditions of European NPPs.

In the context of the aforementioned criteria, some potentially relevant Euratom FP7 projects are excluded on the basis of their technology focus. Such projects include LEADER and HELIMNET, which are primarily concerned with liquid metal technologies, as well as MATTER and GETMAT on the basis that the design requirements of the innovative reactors with which they are concerned are beyond those of the European NPP fleet currently in operation. While the findings of FP7 projects such as PERFORM60 and LONGLIFE have been taken into account, the amount of available outputs from these projects – especially in the case of PERFORM60 – is limited. Thus, the larger proportion of research to which consideration has been given in this synthesis report originates from Euratom FP4, FP5 and FP6.