About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
|
Transmutation Effects in Fusion Reactor Materials: Critical Challenges & Path Forward
|
Presentation Title |
Transmutation Effects in Fine Grained Tungsten: Gas Behavior and the Role of Grain Boundaries |
Author(s) |
Jason Trelewicz |
On-Site Speaker (Planned) |
Jason Trelewicz |
Abstract Scope |
In tungsten, which has emerged as the primary armor material for the divertor in ITER and a likely candidate for early demonstration reactors, neutron irradiation promotes embrittlement and property degradation with enhanced production of gaseous (H/He) and solid (Re/Os) transmutation products under the high-energy fusion neutron spectrum. In this presentation, these effects are reviewed with an emphasis on research opportunities in grain boundary engineered tungsten. A focused set of experiments on the implications of helium gas production for the mechanical behavior is described, employing fine grained tungsten specifically to probe the role of grain boundaries. We show that the formation of grain boundary cavities is correlated to a reduction in hardness, which is recovered with increasing fluence due to classical irradiation hardening. Insights from molecular dynamic simulations demonstrate that the observed softening can be attributed to stress-assisted grain boundary bubble coalescence and enhanced strain accommodation within the grain boundaries. |
Proceedings Inclusion? |
Planned: |
Keywords |
Nuclear Materials, Mechanical Properties, Environmental Effects |