Skip to main content Accessibility help

Transitions of Shear Resistance in a Single-Asperity Contact

  • J. A. Hurtado (a1) and K.-S. Kim (a1)


The shear force required to emit circular dislocation loops from the edge of a circular adhesive-contact zone is calculated analytically as a function of contact-zone radii. The emission condition is based on the balance of the configurational force and the Peierls force on a dislocation loop initiated at the edge of the adhesive contact zone. The analysis suggests that there is a transition, for a nanometer-scale single-asperity contact, from concurrent (mobile- dislocation-free) slip to single-dislocation-assisted (SDA) slip. The nanometer-scale friction stress (shear force required for slip/contact area), which experimentally is observed independent of normal loading and contact-zone size, is believed to be the stress required for concurrent slip. The analysis also predicts a second transition from SDA slip to multiple-dislocation-cooperated (MDC) slip at the scale of tens of micrometers in contact size. The friction stress at this large length scale has also been observed experimentally to be independent of normal loading and contact size; however, the friction stress at the nanometer scale is about 30 times that at the scale of tens of micrometers. The analysis is consistent with these experimental observations.



Hide All
1. Bowden, F.P. and Tabor, D., The Friction and Lubrication of Solids, Clarendon Press, Oxford, England, 1950.
2. Homola, A.M., Israelachvili, J.N., McGuiggan, P.M. and Gee, M.L., Wear 136, p. 65 (1990).
3. Carpick, R.W., Agrait, N., Ogletree, D.F. and Salmeron, M., J. Vac. Sci. Technol. B 14, p.1289 (1996); Langmuir 12, p.3334 (1996).
4. Carpick, R.W., Ogletree, D.F. and Salmeron, M., Appl. Phys. Lett. 70, p.1548 (1997).
5. Lantz, M.A., O'Shea, S.J., Welland, M.E. and Johnson, K.L., Phys. Rev. B 55, p.10776 (1997).
6. Enachescu, M., van den Oetelaar, R.J.A., Carpick, R.W., Ogletree, D.F., Flipse, C.F.J. and Salmeron, M., Phys. Rev. Lett. 81, p.1877 (1998).
7. Meyer, E., Ltithi, R., Howald, L., Bammerlin, M., Guggisberg, M. and Gtintherodt, H.- J., J. Vac. Sci. Technol. B 14, p.1285 (1996).
8. Hurtado, J.A. and Kim, K.- S., Proc. R. Soc. Lond., submitted.
9. Hirth, J. and Lothe, J., Theory of Dislocations, second edition, John Wiley & Sons, 1982.
10. Rice, J.R. and Thomson, R., Phil. Mag. 29, p.73 (1973).
11. Savkoor, A.R., Dry adhesive contact of elastomers, M. Engng dissertation, Tech. University Delft, The Netherlands (1987).
12. Kim, K.-S., McMeeking, R.M. and Johnson, K.L, J. Mech. Phys. Solids 46, p.243 (1998).


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed