Direct atomistic modeling of solute drag by moving grain boundaries. (1st October 2020)

• Record Type: Journal Article
• Authors: Koju, R.K.; Mishin, Y.
• Is Part Of: Acta materialia. Volume 198(2020)
• Page Start: 111
• Page End: 120
• Publication Date: 2020-10-01
• Subjects: Molecular dynamics -- Grain boundary -- Vacancies -- Solute drag; Materials -- Periodicals; Materials science -- Periodicals; Materials -- Mechanical properties -- Periodicals; Metallurgy -- Periodicals; Chemistry, Inorganic -- Periodicals; 620.112
• DOI: 10.1016/j.actamat.2020.07.052
• Languages: English
• ISSNs: 1359-6454

Abstract

Graphical abstract: Abstract: We show that molecular dynamics (MD) simulations are capable of reproducing the drag of solute segregation atmospheres by moving grain boundaries (GBs). Although lattice diffusion is frozen out on the MD timescale, the accelerated GB diffusion provides enough atomic mobility to allow the segregated atoms to follow the moving GB. This finding opens the possibility of studying the solute drag effect with atomic precision using the MD approach. We demonstrate that a moving GB activates diffusion and alters the short-range order in the lattice regions swept during its motion. It is also shown that a moving GB drags an atmosphere of non-equilibrium vacancies, which accelerate diffusion in surrounding lattice regions.