About this Abstract |
Meeting |
2nd World Congress on High Entropy Alloys (HEA 2021)
|
Symposium
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2nd World Congress on High Entropy Alloys (HEA 2021)
|
Presentation Title |
Modeling Dislocation Dynamics in Refractory Multi-principal Element Alloys |
Author(s) |
Lauren Fey, Shuozhi Xu, Yanqing Su, Abigail Hunter, Irene Beyerlein |
On-Site Speaker (Planned) |
Lauren Fey |
Abstract Scope |
There is growing experimental and modelling evidence that dislocations in refractory multi-principal element alloys (MPEAs) behave in distinct ways from dislocations in conventional alloys. We develop a phase-field dislocation dynamics model for refractory MPEAs that incorporates variable glide resistances, differences between screw and edge dislocation behavior, and different crystallographic slip modes. The mesoscale model is informed by atomistic calculations and applied to study dislocation glide and multiplication in a model MPEA, MoNbTi. The inherent variability in dislocation glide resistance due to the disordered lattice causes the formation of athermal kink-pairs on screw dislocations, creating a wavy morphology during dislocation glide and probabilistic glide stresses. Our calculations show that the stresses required for screw dislocation glide are similar across several slip plane types, increasing the potential pathways for dislocations. |
Proceedings Inclusion? |
Undecided |