Molecular dynamics study of strain-induced diffusivity of nitrogen in pure iron nanocrystalline

R Mohammadzadeh and N Razmara and F Razmara, PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS, 463, 123-130 (2016).

DOI: 10.1016/j.physa.2016.07.012

In the present study, the self-diffusion process of nitrogen in pure iron nanocrystalline under strain conditions has been investigated by Molecular Dynamics (MD). The interactions between particles are modeled using Modified Embedded Atom Method (MEAM). Mean Square Displacement (MSD) of nitrogen in iron structure under strain is calculated. Strain is applied along 1120 and 0001 directions in both tensile and compression conditions. The activation energy and pre-exponential diffusion factor for nitrogen diffusion is comparatively high along 0001 direction of compressed structure of iron. The strain-induced diffusion coefficient at 973 K under the compression rate of 0.001 angstrom/ps along 0001 direction is about 6.72E-14 m(2)/s. The estimated activation energy of nitrogen under compression along 0001 direction is equal to 12.39 kcal/mol. The higher activation energy might be due to the fact that the system transforms into a more dense state when compressive stress is applied. (C) 2016 Elsevier B.V. All rights reserved.

Return to Publications page