Molecular Dynamics Simulations of Phosphorus Migration in a Grain Boundary of α-Iron

  • Ken-ichi EbiharaEmail author
  • Tomoaki Suzudo
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)


Phosphorus causes steels grain boundary embrittlement, which is considered to influence the ductile-brittle transition in reactor pressure vessel steels. In order to develop a rate theory model for calculating grain boundary phosphorus segregation based on atomistic processes, so far, we have evaluated the diffusion coefficient of phosphorus migration due to dragging by vacancies and self-interstitial atoms and the influence of thermal grain boundary fluctuation and of strain around grain boundaries to the phosphorus migration. However, the atomistic process that phosphorus atoms de-trap from grain boundaries, which is essential to the rate theory model, is still unclear. In this study, we simulated the migration of a phosphorus atom in the region of a Σ3(111) symmetrical tilt grain boundary using molecular dynamics and evaluated the migration barrier energy. From the results, we found that phosphorus atoms can migrate through gaps between iron atoms inside the grain boundary region.


Grain boundary Phosphorus segregation Molecular dynamics simulation Trapping and de-trapping Phosphorus migration 



This work is partly supported by JSPS KAKENHI Grant Number JP15K06429.


  1. 1.
    Review of phosphorus segregation and intergranular embrittlement in reactor pressure vessel steels (PWRMRP-19): PWR material reliability project, TR-114783 (EPRI, CA, 2000)Google Scholar
  2. 2.
    Ebihara K, Suzudo T, Yamaguchi M (2017) Modeling of phosphorus transport by interstitial dumbbell in α-iron using first-principles-based kinetic Monte Carlo. Mater Trans 58(1):26–32. Scholar
  3. 3.
    Ebihara K, Suzudo T (2018) Atomistic simulation of phosphorus segregation to Σ3(111) symmetrical tilt grain boundary in α-iron. Model Simul Mater Sci Eng 26:065005. Scholar
  4. 4.
    Honeycutt JD, Andersen HC (1987) Molecular dynamics study of melting and freezing of small Lennard-Jones clusters. J Phys Chem 91:4950–4963Google Scholar
  5. 5.
    Plimpton S (1995) Fast parallel algorithms for short-range molecular dynamics. J Comput Phys 117:1–19. Scholar
  6. 6.
    Ackland GJ, Mendelev MI, Srolovitz DJ, Han S, Barashev A (2004) Development of an interatomic potential for phosphorus impurities in α-iron. J Phys Condens Matter 16:S2629-42. Scholar
  7. 7.
    Stukowski A (2010) Visualization and analysis of atomistic simulation data with OVITO-the open visualization tool. Model Simul Mater Sci Eng 18:015012. Scholar
  8. 8.
    Yamaguchi M, Nishiyama Y, Kaburaki H (2007) Decohesion of iron grain boundaries by sulfur or phosphorous segregation: first-principles calculations. Phys Rev B 76:035418-1-5. Scholar
  9. 9.
    Gao F, Heinisch H, Kurtz RJ (2006) Diffusion of He interstitials in grain boundaries in α-Fe. J Nucl Mater 351:133–140.
  10. 10.
    Meslin E, Fu C-C, Barbu A, Gao F, Willaime F (2007) Theoretical study of atomic transport via interstitials in dilute Fe-alloys. Phys Rev B 75:094303-1-8. Scholar
  11. 11.
    Domain C, Becquart CS (2005) Diffusion of phosphorus in α-Fe: an ab initio study. Phys Rev B 71:214109-1-13. Scholar

Copyright information

© The Minerals, Metals & Materials Society 2020

Authors and Affiliations

  1. 1.Japan Atomic Energy AgencyTokai-mura, Naka-gunJapan

Personalised recommendations