On stickiness of multiscale randomly rough surfaces

A new stickiness criterion for solids having random fractal roughness is derived using Persson's theory with DMT-type adhesion. As expected, we find stickiness, i.e., the possibility to sustain macroscopic tensile pressures or else non-zero contact area without load, is not affected by the truncation of the PSD spectrum of roughness at short wavelengths and can persist up to roughness amplitudes orders of magnitude larger than the range of attractive forces. With typical nanometer values of the latter, the criterion gives justification to the well-known empirical Dalhquist criterion for stickiness that demands adhesives to have elastic modulus lower than about 1 MPa.

https://www.tandfonline.com/doi/full/10.1080/00218464.2019.1685384
 

G. Violano, L. Afferrante, A. Papangelo & M. Ciavarella (2019), On stickiness of multiscale randomly rough surfaces, The Journal of Adhesion, DOI:10.1080/00218464.2019.1685384 https://www.researchgate.net/profile/Antonio_Papangelo