HCP Grain Boundary Motion Via Artificial Driving Force Methods
Shawn P. Coleman (1), Matthew C. Guziewski (1,2), Christopher R. Weinberger (2)
1 Weapons and Materials Research Directorate, U.S. Army Research Laboratory Aberdeen, MD 21005
2 Department of Mechanical Engineering, Colorado State University, Fort Collins, CO 80523
Artificial driving force methods are expanded to enable high throughput investigations of hexagonal close-packed grain boundary motion via molecular dynamics. To drive the motion of grain boundaries constructed from bicrystal models, an orientation dependent energy term to an existing potential to impose additional forces isolated on the grain boundary atoms. The artificial forces acting on boundary atoms promote their reorientation to the lower energy configuration, thus moving the boundary plane towards the higher energy grain. The artificial driving force methods show consistent results as compared to more physically based shear simulations, but are not restricted to shear coupled grain boundary geometries. Thus, high throughput calculations for Mg grain boundary motion are established and the resulting mobility values are incorporated into a novel grain boundary structure-property database.