enabling Sixty Years creep-fatigue life of the NExt generation nuclear Reactors 'SYNERgy'

The science and engineering of materials have been fundamental to the success of nuclear power to date. They are also the key to the successful deployment and operation of a new generation of nuclear reactor systems. The next-generation nuclear reactors (Gen IV) operating at temperatures of 550C and above have been previously studied to some extent and in many cases experimental or prototype nuclear systems have been operated. For example, the UK was the world-leading nation to operate the Dounreay experimental sodium-cooled fast nuclear reactor (SFR) for ~19 years and a prototype fast reactor for ~20 years. However, even for those SFRs with in total of 400 reactor-years international operating experience, their commercial deployment is still held up. A formidable challenge for the design, licensing and construction of next-generation Gen IV SFRs or the other high-temperature nuclear reactors is the requirement to have a design life of 60 years or more.

The key degradation mechanisms for the high-temperature nuclear reactors is the creep-fatigue of steel components. When structural materials are used at high temperature, thermal ageing and inelastic deformation lead to changes in their microstructures. The creep and creep-fatigue performance of structural materials are limited by the degradation of microstructures. The underlying need is to develop improved understanding and predictive models of the evolution of the key microstructural features which control long-term creep performance and creep-fatigue interaction. This Fellowship will use an integrated experimental and modelling approach covering different length and time scales to understand and predict the long-term microstructural degradation and creep-fatigue deformation and damage process. I will then use the new scientific information to make significant technological breakthroughs in predicting long-term creep-fatigue life that include microstructural degradation process. I will thereby realise a radical step beyond the current phenomenological or a functional form of constitutive models which received very limited success when extrapolated to long-term operational conditions. This research will put me and the UK at the forefront of nuclear fission research.

This Fellowship will enable the 60 years creep-fatigue life of the next-generation high-temperature nuclear systems by developing a materials science underpinned and engineering based design methodology and implement it into future versions of high-temperature nuclear reactor design codes. In consequence, Gen IV reactor technologies will become commercially viable and Gen IV SFRs will be built globally to provide an excellent solution for recycling today's nuclear waste. This fellowship aims to influence the international organisations responsible for the next-generation nuclear design codes and gaining an early foothold in the international nuclear R&D via this research will give the best chance to secure Intellectual Property and return long term economic gains to our UK.

The February 2017 Final Report by the UK's Nuclear Innovation and Research Advisory Board (NIRAB) has publicised its final set of nuclear research programme recommendations which was made to the Ministers. These recommendations are focused on closing gaps associated with new reactor systems which, in the absence of action, would prevent the UK realising the economic and industrial potential in low carbon nuclear energy. This ambitious Fellowship is aimed at developing fundamental scientific understandings of long-term creep-fatigue aspect that are needed to design and build advanced and new nuclear fission reactors (Gen IV fast reactors in particular) in an accelerated and cost effective way, with emphasis on ever increasing safety. This Fellowship will put me and the UK at the forefront of research in the field, importantly having far-reaching economic and societal impacts.

Impact 1: International Collaboration on Future Nuclear Research

This project is of strong relevance and interest to the UK's stakeholders of nuclear research and industry, and will return long term economic gains to the UK. The NIRAB report has emphasised several times that there is a need to maintain and build capability and to re-engage in major international development programmes for the development of future nuclear reactor. To this end, I have enlisted the participation of two major Gen IV International Partners (Europe and China) in addition to the UK's key nuclear groups who will be directly involved into performing research and delivering impact. The EERA JPNM is a European nuclear materials group of more than 40 participants, aims to improve safety and sustainability of Nuclear Energy. The China Structural Integrity Consortium (more than 50 members) aims to integrate the expertise ranging from materials development, advanced manufacturing to components design and life assessment. This Fellowship will support and accelerate the commercial deployment of world's first Gen IV sodium-fast reactors in both the Europe and China. I aim to further strengthen my links with these international project partners via exchange of personnel and their close involvement in this Fellowship. Fostering international collaboration in nuclear field will enable the UK to enter into major international initiatives and will underpin the UK's nuclear industry strategy. I anticipate that this research will enable the UK becoming a key partner of choice in commercialising advanced and new reactor systems worldwide and will place the UK at the top table of nuclear nations.

Impact 2: Sustaining Skills and Capability

The second major impact of this Fellowship will be in developing the next generation of high-temperature nuclear researchers and a future leader in the field. The urgency of the situation is underlined by the UK's high-temperature nuclear workforce approaching retirement and the consequent possibility of losing important knowledge particularly in the field of UK's historical and world-renowned high-temperature and fast nuclear reactors. This Fellowship will connect a team of talented postgraduate and postdoctoral researchers with the senior experts in nuclear industry to facilitate knowledge transfer. All the young researchers will be encouraged and supported to engage with the world-leading nuclear research groups. These young researchers are likely to be highly valued in their future career in academia or industry, with corresponding benefit to the UK knowledge economy for performing future international R&D programmes.

Impact 3: Meeting CO2 Emission Reduction Targets for 2050

The outputs from this Fellowship will support the new build fleet, importantly creating a platform to support advanced reactor development in the longer term. The scientific and technological breakthrough achieved in this research will play a significant role in the UK's and international future low carbon electricity innovation.