Letter | Published:

Surface Self-diffusion of Tungsten

Nature volume 222, pages 977979 (07 June 1969) | Download Citation

Subjects

Abstract

HERE we describe briefly the results of some recent experiments on the diffusion of tungsten atoms over an atomically clean surface of tungsten. The method used was that of following the decay with time of a series of sinusoidal grooves in the surface of the specimen at various temperatures. Mullins1 has shown that the depth of the grooves at a time t is given by where ω = (2φ/the wavelength of the groove). The terms in the exponent are the contributions to the smoothing process due to evaporation, volume diffusion and surface diffusion respectively. A, B and C are functions of temperature, so that by careful choice of temperature and wavelength it is possible to make surface diffusion the dominant mechanism of mass transfer, corrections being made for the other two processes. B is given by Ds = D0 exp (−QS/RT), where Qs is the activation energy for surface diffusion, vs is the specific surface free energy, Ω the atomic volume and N the number of atoms per unit surface area. Thus from the decay constant in equation (1) it is possible to obtain the surface self-diffusion coefficient, Ds.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

References

  1. 1.

    , J. Appl. Phys., 30, 77 (1959).

  2. 2.

    , and , J. Appl. Phys., 39, 3480 (1968).

  3. 3.

    , and , J. Appl. Phys., 39, 3476 (1968).

  4. 4.

    , Rev. d'Optique, 39, 291 (1960).

  5. 5.

    , Canad. J. Phys., 37, 787 (1959).

  6. 6.

    , , , , , and , Phys. Rev., 117, 1452 (1960).

  7. 7.

    , in Fundamentals of Gas-Surface Interactions (edit. by Saltsburg, H.), 42 (Academic Press, 1967).

  8. 8.

    , and , Surface Sci., 12, 109 (1968).

  9. 9.

    , and , Ann. Physik, 1, 153 (1947).

  10. 10.

    , Energetics in Metallurgical Phenomena, 2 (edit. by Mueller W. M.) (Gordon and Breach Science Publishers, NY, 1965).

  11. 11.

    , and , Trans. A.I.M.E., 230, 123 (1964).

  12. 12.

    , J. Chem. Phys., 14, 441 (1946).

Download references

Author information

Author notes

    • F. P. BOWDEN

    Professor Bowden died recently.

Affiliations

  1. Surface Physics, Cavendish Laboratory, University of Cambridge.

    • F. P. BOWDEN
    •  & K. E. SINGER

Authors

  1. Search for F. P. BOWDEN in:

  2. Search for K. E. SINGER in:

About this article

Publication history

Received

Revised

Published

DOI

https://doi.org/10.1038/222977b0

Further reading

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.