| About this Abstract |
| Meeting |
MS&T24: Materials Science & Technology
|
| Symposium
|
Grain Boundaries, Interfaces, and Surfaces: Fundamental Structure-Property-Performance Relationships
|
| Presentation Title |
The Role of Grain Boundary Dislocations in the Deformation of Polycrystalline Materials |
| Author(s) |
Yan Huang |
| On-Site Speaker (Planned) |
Yan Huang |
| Abstract Scope |
Steady state deformation by plane strain compression at temperatures from 200°C to -195°C in a dilute single-phase aluminium alloy has been characterized to understand the critical contribution of grain boundary dislocations to the plastic flow of the material. Although steady state flow stress and grain size remains constant as a function of strain, continuous loss of grain boundaries occurs as an essential feature at steady state. The temperature dependence of the steady state grain size is substantially weaker than that predicted from conventional diffusion-controlled grain boundary migration and a constant grain size can only be maintained by invoking an athermal mechanism. A physical model, based on grain boundary dislocation emission, is developed to describe the kinetics of steady state deformation and, more generally, the role of grain boundary dislocations in the plastic deformation of polycrystal materials. |