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arXiv · 0708.2264

Influence of random roughness on the adhesion between metal surfaces due to capillary condensation

P. J. van Zwol·G. Palasantzas·J. Th. M. De Hosson
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Abstract

The capillary force was measured by atomic force microscopy between a gold coated sphere mounted on a cantilever and gold surfaces with different roughness. For smooth surfaces the capillary adhesive force surpasses in magnitude any dispersion, e.g. van der Waals/Casimir, and/or electrostatic forces. A substantial decrease in the capillary force was observed by increasing the roughness ampltitude a few nanometers between 1-10 nm. From these measurements two limits can be defined: a smooth limit where a closely macroscopic size contact surface interacts through the capillary force, and the rough limit where only a few asperities give a capillary contribution.

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P. J. van Zwol, G. Palasantzas, J. Th. M. De Hosson. 2007-08-16. Influence of random roughness on the adhesion between metal surfaces due to capillary condensation. https://doi.org/10.1063/1.2768919

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