Bearing-area adhesion model
Enter surface, material and interaction parameters. Results update immediately.
Pressure–separation response
Method and background
This calculator estimates adhesion pressure and pull-off pressure between two elastic, nominally flat rough surfaces. It is based on the simplified bearing-area theory developed by Professor Michele Ciavarella.
The response combines an exponentially decaying repulsive contribution with the increase in attractive interaction area as separation decreases.
p/pth = (3/8γ)(q₀hrmsE*/pth) exp[−u/(γhrms)] − (1/2k){erfc[(u−Δr)/(√2hrms)] − erfc[u/(√2hrms)]}
The entered-separation result uses the model’s zero-separation repulsive term; pull-off is the minimum over 201 curve points from 0 to 5hrms. Constants: γ = 0.45 and k = 2. Negative pressure is tensile.
Further background: Ciavarella’s simplified adhesion theory. Questions about the model may be directed to [email protected].
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