About this Abstract |
Meeting |
2020 TMS Annual Meeting & Exhibition
|
Symposium
|
High Entropy Alloys VIII
|
Presentation Title |
J-15 (Digital): Atomistic Modeling of Dislocations in a Random High-entropy Alloy |
Author(s) |
Diana Farkas, Roberto Pasianot |
On-Site Speaker (Planned) |
Diana Farkas |
Abstract Scope |
The core structure and mobility of dissociated ½<110> dislocations in a model FCC high entropy alloy is studied using atomistic simulations. The simulations utilize model embedded-atom-method (EAM) potentials for al five component random equiatomic alloy, and a corresponding “average atom” potential. The dislocation line that corresponds to minimum energy in the random alloy is not straight but curvy and significant variations in dissociation distances are found. This effect is more significant for edge dislocations than for screw dislocations. Calculations also show that both the stable and unstable stacking fault energies vary according to the local composition of the alloy. A range of Peierls stresses cis found for the dislocations in the alloy, depending on the local composition. Most importantly, these stresses are significantly higher than in the pure components or those computed using an average atom potential. This effect is analyzed in terms of the core structure of the dislocations. |
Proceedings Inclusion? |
Planned: Supplemental Proceedings volume; Planned: Supplemental Proceedings volume |