|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Coupling Experiments and Modeling to Understand Plasticity and Failure
||Improved Understanding of the Portevin–Le Châtelier Effect though Modelling Using Discrete Diffusion Coupled with Discrete Dislocation Dynamics
||William White, Daniel Balint, Ben Britton
|On-Site Speaker (Planned)
When solutes cluster at dislocations, strong elastic interactions can impede slip. Dislocations remain immobilised until the shear stress acting upon the cluster breaches a critical value, or via thermally activated escape mechanisms. At particular temperatures, strain rates and solute concentrations, this process can occur repeatedly causing serrated plastic flow and decreased ductility, a phenomenon known as the Portevin–Le Châtelier (PLC) effect. A planar discrete dislocation plasticity (DDP) model is used to study this effect, by introducing a diffusing solute population. Solutes, treated as an ideal gas diffusing in an elastic continuum, are characterized by their concentration, diffusivity and effective dislocation trapping area and strength. It is shown that the model captures the qualitative nature of the PLC effect. Furthermore, it is observed that increasing solute diffusivity increases the magnitude and decreases the frequency of the serrations recorded in the stress-strain curve. Anisotropy effects are also considered.
||Planned: Supplemental Proceedings volume