Tribology Letters

, 64:14 | Cite as

On the Contact Area of Nominally Flat Hertzian Contacts

Original Paper

Abstract

In a recent paper, Pastewka and Robbins (Appl Phys Lett 108:221–601, 2016) state an analytical expression for the real contact area of a Hertzian tip with small-scale roughness. We confirm that their formula predicts real contact areas quite well—with less than 10 % error. Nonetheless, the complementary contact area does not show the proper scaling to the continuum results at large loads. This shortcoming is fixed in the present work by abandoning a mean-field approximation made in the original work. Analytical results can even be made essentially perfect with a relation giving the accurate dependence of contract area on pressure for contacts between solids with nominally flat surfaces.

Keywords

Contact mechanics Surface roughness Analysis and models Molecular dynamics 

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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  1. 1.Department of Materials Science and EngineeringSaarland UniversitySaarbrückenGermany

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