Strain mapping in nanocrystalline grains simulated by phase field crystal model

Abstract

In recent years, the phase field crystal (PFC) model has been confirmed as a good candidate to describe grain boundary (GB) structures and their nearby atomic arrangement. To further understand the mechanical behaviours of nanocrystalline materials, strain fields near GBs need to be quantitatively characterized. Using the strain mapping technique of geometric phase approach (GPA), we have conducted strain mapping across the GBs in nanocrystalline grains simulated by the PFC model. The results demonstrate that the application of GPA in strain mapping of low and high angles GBs as well as polycrystalline grains simulated by the PFC model is very successful. The results also show that the strain field around the dislocation in a very low angle GB is quantitatively consistent with the anisotropic elastic theory of dislocations. Moreover, the difference between low angle GBs and high angle GBs is revealed by the strain analysis in terms of the strain contour shape and the structural GB width.

Keywords:

• strain analysis
• grain boundary
• phase field crystal
• GPA

Acknowledgements

The authors thank the Center for High Performance Computing of Northwestern Polytechnical University, China for computer time and facilities.

Additional information

Funding

This work has been supported by Nature Science Foundation of China [grant number 51371151], National Basic Research Program of China [grant number 2011CB610401], and Free Research Fund of State Key Laboratory of Solidification Processing [100-QP-2014].