|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Hume-Rothery Award Symposium: Alloy Phase Chemistry at the Atomic Level - Opportunities and Challenges
||Prediction of Segregation Induced Precipitation at Dislocations via Atomistic Simulations
||Chad Sinclair, Evgeniya Dontsova, Joerg Rottler
|On-Site Speaker (Planned)
There are many problems in materials science for which mean-field models are inappropriate. An example is precipitation in the vicinity of a dislocation. The presence of the long-range strain field of the dislocation makes both the local thermodynamics and kinetics spatially and temporally complex and not easy to capture without information about the local details of the dislocation. In this work we have used a recent adaptation of the “diffusive molecular dynamics” (DMD) model to examine the precipitation of an ordered phase at edge dislocations in the Al-Mg system. It is found that segregation of Mg lowers the barrier for nucleation of the ordered phase to zero, allowing for a “barrierless” first order transition. It will be shown that this has similarities to, but is distinct from, dislocation induced precipitation in systems exhibiting a chemical spinodal. These results will be compared with experimental observations of ordered phase formation at dislocations.
||Planned: Supplemental Proceedings volume