About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
|
Transmutation Effects in Fusion Reactor Materials: Critical Challenges & Path Forward
|
Presentation Title |
Interaction of Hydrogen/Helium with Grain Boundaries and Dislocations in Tungsten |
Author(s) |
Nithin Mathew, Enrique Martinez, Blas Uberuaga, Danny Perez |
On-Site Speaker (Planned) |
Nithin Mathew |
Abstract Scope |
Tungsten (W) is the primary candidate for divertor material in future fusion reactors. In addition to intake from the fuel, nuclear transmutation reactions lead to formation of H and He in the divertor. Interaction of these H/He with extended defects such as dislocations and grain boundaries (GBs) can have a significant effect on the microstructure and mechanical properties of W divertor. We will present predictions from direct-/accelerated- molecular dynamics simulations on the interactions between H/He with symmetric tilt GBs and dislocations. Segregation of H is found to result in a complex, structure dependent effect on GB mobility. Assuming a disconnection-based mechanism for GB motion, it is shown that the conventional picture of solute-drag dominated Arrhenius kinetics is incomplete. He bubble growth in the vicinity of dislocations results in the formation sessile and glissile loops which, in turn, leads to complex reactions with the existing dislocation and modification of its character. |
Proceedings Inclusion? |
Planned: |
Keywords |
Mechanical Properties, Nuclear Materials, Computational Materials Science & Engineering |