General Approach to Diffusion under a Stress in Metals and Interstitial Alloys

Abstract:

One of the main aims of our work is to obtain general equations for the diffusion fluxes under strain that give the possibility for using these equations at low temperatures, as in this case the strain influence on the diffusion fluxes is manifested in maximal degree. Our approach takes into consideration that the strains can alter the surrounding atom configuration near the jumping atom and consequently the local magnitude of the activation barrier and a rate of atom jumps. The approach is derived under assumptions that the total energy depends on the pair distances only and the attempt frequencies are the same for all jumps. The rates of atom jumps in different directions define the flux density of the defects. Now we take into account that the strain tensor is different at the saddle point and at the rest atom position, that differentiates our approach from previous ones. As a result, general equations for the vacancy fluxes and impurity fluxes are obtained for fcc and bcc metals. These equations differ significantly from those obtained earlier.

• Periodical: Defect and Diffusion Forum (Volume 363)
• Pages: 112-119
• DOI: https://doi.org/10.4028/www.scientific.net/DDF.363.112
• Online since: May 2015
• Authors: Andrei Nazarov*, Alexander Mikheev
• Keywords: Diffusion, Elastic Strain, Impurity, Interstitial, Microscopic Approach, Vacancy

References

[1] Shewmon P G 1989 Diffusion in solids (2nd ed. Warrendale, PA: TMS).

[2] Girifalco L A and Welch D O 1967 Point Defects and Diffusion in Strained Metals (Gordon and Breach Science Publishers, New York).

[3] J. Philibert, Metal Physics and Advanced Technologies 21 (1999) 3–7.

[4] P. H. Dederichs, K. Schroeder, Phys. Rev. B 17 (1978) 2524–2536.

[5] A.V. Nazarov, A. A. Mikheev, Def. Diff. Forum 143-147 (1997) 177–184.

[6] A.V. Nazarov, A. A. Mikheev, Physica Scripta T108 (2004) 90–94.

[7] A.V. Nazarov, A.A. Mikheev, J. Phys.: Condens. Matter 20 (2008) 485203. 1–485203. 5.

[8] Andrei Nazarov, Alexander Mikheev, Irina Valikova and Alexander Zaluzhnyi, Solid State Phenomena 172-174 (2011) 1156–1163.

DOI: 10.4028/www.scientific.net/ssp.172-174.1156

[9] A.V. Nazarov, M.G. Ganchenkova, A.A. Mikheev, Def. Diff. Forum 194-199 (2001) 49–55.

[10] M. W. Finnis and J.E. Sinclair, Phil. Mag. A 50 (1984) 45–53.

[11] H. R. Glyde, Rev. of Mod. Phys. 39 (1967) 373–385.

[12] I.V. Valikova, A. V. Nazarov, Phys. of Metals and Metallography 105 (2008) 544–552.

[13] I.V. Valikova, A. V. Nazarov, Phys. of Metals and Metallography 109 (2010) 220–226.

[14] Alexander Mikheev, Andrei Nazarov, Irina Valikova and Alexander Zaluzhnyi, submitted to Def. Diff. Forum, this issue (2015).