Computational Design of Novel, Radiation Resistant Fusion Materials

摘要

The promise of fusion as a viable 21st century energy source requires the development of advanced structural (MFE and IFE) and optical (IFE) materials that are capable of withstanding the harsh radiation environment that leads to the degradation of physical and mechanical properties. Materials in fusion environments must be able to handle 14 MeV neutrons produced from Deuterium-Tritium nuclear reactions, as well as the insoluble He and reactive H gases that lead to swelling and embrittlement. Additionally, with the requirement of very high thermal loads makes the development of new advanced materials a formidable challenge. The scope of this study was to determine the feasibility of using atomistic simulations to predict the radiation response of novel materials engineered with potentially self-healing properties to survive in radiation environments over very long time-scales. The class of materials that shows promise is what is called a nanocrystalline material. Nanocrystalline materials are defined as those having very fine grains on the order of several to tens of nanometers in size, and consequently very high grain-boundary to volume ratio. Experimental observations [1] suggests that these grain-boundary networks can act as sinks for defects and hence promote self-repair.