The grain boundary mobility tensor
Abstract
Defects and microstructures have a profound impact on material strength and ductility. Microstructure engineering can enhance/trade-off between these properties. One of the key parameters that dictates microstructure evolution is grain-boundary mobility. We demonstrate the fundamental nature of the mobility, reconciling a wide range of observations in a consistent model. We argue that the mobility is, in general, a tensor (classically, it is a scalar) and determine all of its components. We do this by combining molecular-dynamics simulations and the development of a statistical mechanics-based disconnection (line defects in grain boundaries) model. The tensor nature of the mobility explains which grain-boundary characteristics are materials properties and which are not and demonstrates that stress generation always slows grain growth.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 18, 2020
- Source ID
- 10.1073/pnas.1920504117
Entities
People
- David J Srolovitz
- Jian Han
- Kongtao Chen
- Xiaoqing Pan
Organizations
- Army Research Office
- City University of Hong Kong
- University of California
- University of Pennsylvania