New standards for nuclear reactor designs
The increased interest in nuclear energy for electricity generation as well as non-electrical applications is becoming more and more evident as new nuclear plants are being built in several countries – including emerging and developing countries. However, before starting the construction of Generation IV reactors, safety concerns need to be addressed. Researchers initiated the MATTER (Materials testing and rules) project to update the existing standard procedures for evaluating the behaviour of materials under the operating conditions of such systems. The consortium was composed of 26 partners (24 were European, one was Korean and one Australian). The MATTER team analysed key materials' properties for new reactors and aimed to demonstrate up to 60 years' lifetime. Specifically, low strain rate and small punch tests were carried out on irradiated material samples. They also developed new procedures to characterise fracture toughness, creep in thin-walled components and liquid-metal corrosion. Researchers populated an extensive database with all the experimental test data. Data from tests of potential degradation mechanisms such as thermal ageing, liquid-metal/steel interactions and irradiation damage were carefully analysed before they were added to the database. In addition, base and filler materials, as well as welding technologies, were tested to improve the toughness of reactor components. At the end of the four-year project, a series of comprehensive summaries were delivered. This included scientific reviews, database information, proposals for new design rules to answer some of the most pressing needs of the MYRRHA (Multipurpose Hybrid Research Reactor for High-tech Applications) and the ASTRID (Advanced Sodium Technological Reactor for Industrial Demonstration) projects. MATTER recognised that the available European standards for material testing and components design do not cover new materials to be used in generation IV reactors nor issues arising from their operating conditions. Successful development of new measures will foster the safety and sustainability of Generation IV reactors and make the EU a world leader in this promising new field.
Keywords
Nuclear reactor, screening methods, materials certification, electricity generation, MATTER
