|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Grain Boundaries and Interfaces: Metastability, Disorder, and Non-Equilibrium Behavior
||Model for Grain Boundary Stress Field Evolution due to Dislocation-grain Boundary Interactions and Influence on Subsequent Slip Transmission
||Darshan Bamney, Laurent Capolungo, Douglas E. Spearot
|On-Site Speaker (Planned)
Dislocation transmission across grain boundaries (GBs) often results in the formation of residual dislocations on the GB plane. In this work, a hybrid disclination-dislocation approach is introduced to model the regression of the GB stress state from equilibrium to nonequilibrium due to the incorporation of residual dislocations during coherent dislocation transmission. The model considers specifically time increments attributable to the dislocation source. The incorporation of residual dislocations causes altered screening characteristics in the NEGB stress field, which leads to locations of high resolved shear stress and low binding stress on the outgoing slip system. This model is implemented into a discrete dislocation dynamics code to simulate the influence of NEGB stress fields, conditioned by the slip transmission history, on subsequent dislocation transmission. DDD simulations reveal that the critical shear stress for dislocation transmission reduces with increased density of residual dislocation incorporation on the GB.
||Computational Materials Science & Engineering, Mechanical Properties, Other