Symposium

M15: Plasticity across the scales – From microstructure changes to bulk mechanical behavior

Belongs to:
TopicM: Modelling and Simulation

The macroscopic mechanical behavior of metals emerges from the complex interactions of multiple phenomena occurring at different scales all contributing to plasticity, such as dislocation glide, phase transitions and twinning. It is possible to investigate the elementary mechanisms by using atomistic methods such as Density Functional Theory and Molecular Dynamics in order to study dislocations or interface structure and mobility. Albeit capable of achieving quantum-accuracy, the usage of atomistic methods is limited in terms of the accessible computational time and simulation  size, which prohibits the simulation of complex phenomena involving multiple dislocations and low-symmetry interfaces. To account for such a complexity, it is thus necessary to adopt mesoscale approaches, like discrete dislocation plasticity or dislocation density-based continuum theories that describe the dislocation flow through transport equations. In order to predict dislocation behavior, it is however necessary to incorporate input based on the lower, discrete scales (atomistics and discrete dislocations). Tailored small or mesoscale experiments can be used to validate those models and the employed simulation method can simultaneously help to understand the experimental observations.

The focus of this symposium is on the employment of appropriate techniques as well as the coarsening of the small scale plasticity behavior originating from small-scale modeling or experiments, by means of multi-scale computational and/or (semi-)analytical models. Examples include dislocation core effects, dislocation junction formation, phase changes, interfaces and grain boundaries in polycrystals, hardening, and dislocation-precipitate interaction in order to understand the macroscopic mechanical behavior of metals.