| Abstract Scope |
Nanostructured metals are promising candidates as radiation resistant materials due to the high density of interfacial sinks that can absorb and redistribute point defects. In these systems, grain size determines sink density, while grain boundary structure and chemistry define control sink strength. In this talk, we explore the manipulation of these variables in nanocrystalline metals, with a specific focus on accessing thermodynamically-stable grain boundary states or grain boundary complexions. For Cu- and W-rich alloys, grain boundary segregation is used to drive structural disordered to achieve amorphous complexions within the microstructure. These features act as strong defect sinks which are also stable at elevated temperatures. We also explore how compositional patterning near grain boundaries in CrCoNi and NbMoTaW can affect radiation damage tolerance. Atomistic and first-principles modeling are used to investigate grain boundary state as well as the evolution under different stimuli, while real world materials are created with severe plastic deformation and then investigated with transmission electron microscopy. As a whole, this study demonstrates that both sink density and strength are tunable parameters, setting the stage for the manipulation of radiation resistance. |