| About this Abstract |
| Meeting |
2023 TMS Annual Meeting & Exhibition
|
| Symposium
|
Nanostructured Materials in Extreme Environments
|
| Presentation Title |
Uncovering the Transition from Helium Clustering to Bimodal Cavity Distributions in Tungsten |
| Author(s) |
Cormac Killeen, Yang Zhang, David J Sprouster, Jason Trelewicz |
| On-Site Speaker (Planned) |
Cormac Killeen |
| Abstract Scope |
In the characterization of gaseous defects that form due to, e.g., transmutation or ion implantation, it is often difficult to probe the incubation stages of bubble formation. This process involves a transition from defect clustering to the nucleation of bubbles and its biasing to various microstructural features. Here, we explore this transition during helium implantation in tungsten as a function of fluence and temperature using a microstructurally informed multi-modal synchrotron approach. Results indicate that low implantation temperatures favor the formation of small sub-nanometer scale helium clusters irresolvable via TEM but accompanied by nanoscale bubble formation homogeneously distributed between the grain matrix and boundary. Higher temperatures lead to a bimodal distribution of small nanometer intragranular bubbles, larger cavities biased to the grain boundaries, and a decrease in the helium cluster fraction. The mechanisms underpinning the transition with fluence, and implications of irradiation temperature, are discussed using insights from molecular dynamics simulations. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Nuclear Materials, Characterization, High-Temperature Materials |