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Simulations of Nanometer-Thick Lubricating Films

Published online by Cambridge University Press:  29 November 2013

Mark O. Robbins ,
Peter A. Thompson  and
Gary S. Grest
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Hydrodynamics and elastohydrodynamics have been successful in describing lubrication by micron-thick films. However, these continuum theories begin to break down as film thicknesses become comparable to molecular dimensions. An increasing number of applications require an understanding of lubricants in such severely confined geometries. Examples include lubrication of nanoscale bearings in micromachinery or high-density magnetic disk drives, as well as asperity interactions in macroscopic bearings that operate in the mixed lubrication regime.

Development of new experimental and theoretical techniques for studying thin lubricant films has paralleled the growing interest in their properties. The surface force apparatus (SFA) allows normal and shear forces to be measured between atomically flat solid surfaces while their separation is determined to within 0.1 nm using interferometry or capacitance. The contact area in the SFA is typically 100 μm across, much larger than the separation between solid walls. The atomic force microscope (AFM) can be used to explore friction in lubricated contacts whose diameter is comparable to the separation (5 nm). This allows spatial resolution of the frictional force on a molecular scale. Quartz-crystal oscillators have been used to determine the frictional forces between a surface and an adsorbed film of one or more monolayers. Theoretical advances have been aided by the advent of supercomputers that allow thin films to be simulated at the molecular level using molecular dynamics. These new experimental and theoretical techniques reveal a sequence of dramatic changes in the static and dynamic properties of fluid films as their thickness approaches molecular scales.

Type
Nanotribology
Information
MRS Bulletin , Volume 18 , Issue 5 , May 1993 , pp. 45 - 49
Copyright
Copyright © Materials Research Society 1993

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References

1. See for example, Dowson, D. and Higginson, G.R., Elastohydrodynamic Lubrication (Pergamon Press, Oxford, 1966).Google Scholar
2.Horn, R.G. and Israelachvili, J.N., J. Chem. Phys. 75 (1981) p. 1400; R.G. Horn, S.J. Hirz, G. Hadziioannou, C.W Frank, and J.M. Catala, J. Chem. Phys. 90 (1989) p. 6767.CrossRefGoogle Scholar
3.Israelachvili, J.N., J. Colloid Interface Sci. 110 (1986) p. 263.CrossRefGoogle Scholar
4.Israelachvili, J.N., McGuiggan, P.M., and Homola, A.M., Science 240 (1988) p. 189.CrossRefGoogle Scholar
5.Gee, M.L., McGuiggan, P.M., Israelachvili, J.N., and Homola, A.M., J. Chem. Phys. 93 (1990) p. 1895.CrossRefGoogle Scholar
6.Israelachvili, J.N., Intermolecular and Surface Forces, 2nd ed. (Academic Press, London, 1991).Google Scholar
7.Van Alsten, J. and Granick, S., Phys. Rev. Lett. 61 (1988) p. 2570.CrossRefGoogle Scholar
8.Van Alsten, J. and Granick, S., Macromolccules 23 (1990) p. 4856.CrossRefGoogle Scholar
9.Hu, H-W., Carson, G.A., and Granick, S., Phys. Rev. Lett. 66 (1991) p. 2758; S. Granick, Science 253 (1992) p. 1374.CrossRefGoogle Scholar
10.Georges, J.M., Millot, S., Loubet, J.M., Touck, A., and Mazuyer, D., in Thin Films in Tribology, edited by Dowson, D., Taylor, C.M., and Godet, M. (Elsevier, New York, 1993).Google Scholar
11.Mate, C.M., McClelland, G.M., Erlandsson, R., and Chiang, S., Phys. Rev. Lett. 59 (1987) p. 1942.CrossRefGoogle Scholar
12.Meyer, E., Overney, R., Brodbeck, D., Howald, L., Lüthi, R., Frommer, J., and Güntherodt, H-J., Phys. Rev. Lett. 69 (1992) p. 1777.CrossRefGoogle Scholar
13.Watts, E., Krim, J., and Widom, A., Phys. Rev. B 41 (1990) p. 3466.CrossRefGoogle Scholar
14.Thompson, P.A., Brinckerhoff, W.B., and Robbins, M.O., J. Adhesion Sci. Technol., in press.Google Scholar
15.Thompson, P.A. and Robbins, M.O., Phys. Rev. A 41 (1990) p. 6830.CrossRefGoogle Scholar
16.Thompson, P.A. and Robbins, M.O., Science 250 (1990) p. 792.CrossRefGoogle Scholar
17.Robbins, M.O. and Thompson, P.A., Science 253 (1991) p. 916.CrossRefGoogle Scholar
18.Thompson, P.A., Grest, G.S., and Robbins, M.O., Phys. Rev. Lett. 68 (1992) p. 3448.CrossRefGoogle Scholar
19.Magda, J., Tirrell, M., and Davis, H.T., J. Chem. Phys. 83 (1985) 1888.CrossRefGoogle Scholar
20.Schöen, M., Cushman, J., Diestler, D., and Rhykerd, C., J. Chem. Phys. 88 (1988) p. 1394.CrossRefGoogle Scholar
21.Schöen, M., Rhykerd, C.L., Diestler, D., and Cushman, J.H., Science 245 (1989) p. 1223.CrossRefGoogle Scholar
22.Heinbuch, U. and Fischer, J., Phys. Rev. A 40 (1989) p. 1144.CrossRefGoogle Scholar
23.Landman, U., Luedtke, W.D., and Ribarsky, M.W., J. Vac. Sci. Technol. A 7 (1989) p. 2829.CrossRefGoogle Scholar
24.Ribarsky, M.W. and Landman, U., J. Chem. Phys. 97 (1992) p. 1937.CrossRefGoogle Scholar
25.Lupowski, M. and van Swol, F., J. Chem. Phys. 95 (1991) p. 1995.CrossRefGoogle Scholar
26.Rabinowicz, E., Friction and Wear of Materials (Wiley and Sons, New York, 1965).Google Scholar
27.Allen, M.P and Tildesley, D.J., Computer Simulation of Liquids (Clarendon Press, Oxford, 1987).Google Scholar
28.Kremer, K. and Grest, G.S., J. Chem. Phys. 92 (1990) p. 5057.CrossRefGoogle Scholar
29.Toxvaerd, S., J. Chem. Phys. 74 (1981) p. 1998.CrossRefGoogle Scholar
30.Bitsanis, I. and Hadziioannou, G., J. Chem. Phys. 92 (1990) p. 3827.CrossRefGoogle Scholar
31.Stevens, M.J. and Robbins, M.O., J. Chem. Phys. 98 (1993) p. 2319.CrossRefGoogle Scholar
32.Chan, D.Y.C. and Horn, R.G., J. Chem. Phys. 83 (1985) p. 5311.CrossRefGoogle Scholar
33.Grest, G.S. and Cohen, M.H., Advances in Chemical Physics, Vol. 48, edited by Prigogine, E. and Rice, S.A. (Wiley and Sons, New York, 1981) p. 455.CrossRefGoogle Scholar
34.Stevens, M.J., Robbins, M.O., and Belak, J.F, Phys. Rev. Lett. 66 (1991) p. 3004; B.J. Ackerson and N.A. Clark, Phys. Rev. Lett. 46 (1981) p. 123.CrossRefGoogle Scholar
35.Bowden, F.P. and Tabor, D., The Friction and Lubrication of Solids (Oxford University Press, Oxford, 1958).Google Scholar
36.Thompson, P.A., Grest, G.S., and Robbins, M.O., to be published.Google Scholar
37.Thompson, P.A. and Grest, G.S., Phys. Rev. Lett. 67 (1991) p. 1751.CrossRefGoogle Scholar
38.Yoshizawa, H., McGuiggan, P.M., and Israelachvili, J.N., Science 259 (1993) p. 1305.CrossRefGoogle Scholar