Michele Ciavarella Yang Xu Robert L. Jackson
Some Closed-Form Results for Adhesive Rough Contacts Near Complete Contact on Loading and Unloading in the Johnson, Kendall, and Roberts Regime
Journal of Tribology Copyright VC 2018 by ASME JANUARY 2018, Vol. 140 / 011402-1
Recently, generalizing the solution of the adhesiveless random rough contact proposed
by Xu, Jackson, and Marghitu (XJM model), the first author has obtained a model for
adhesive contact near full contact, under the Johnson, Kendall, and Roberts (JKR)
assumptions, which leads to quite strong effect of the fractal dimension. We extend here
the results with closed-form equations, including both loading and unloading which were
not previously discussed, showing that the conclusions are confirmed. A large effect of
hysteresis is found, as was expected. The solution is therefore competitive with Persson’s
JKR solution, at least in the range of nearly full contact, with an enormous advantage in
terms of simplicity. Two examples of real surfaces are discussed.
[DOI: 10.1115/1.4036915]
Keywords: Greenwood–Williamson (GW) model, roughness, adhesion, hysteresis,
fractals