ABSTRACT
Considering the expressions derived above, in addition to the plastic adhesion index k and the roughness exponent a, there are two new dimensionless terms, Ay/(aH) and d/cr, which play important roles in the adhesion of rough surfaces with plastic deformation. Therefore, two dimensionless parameters are introduced as
and d
(32)
(33)
where /x is the ratio of the work of adhesion to the product of the standard deviation of the peak heights and the hardness. The larger the /x, the easier the plastic deformation becomes. The dimensionless parameter r\ is the ratio of the separation between the mean plane and the flat sin-face during loading to the standard deviation of the peak heights. Considering equations (27) and (29), one can see that /x = 1 represents the condition of plastic deformation at zero load for exponential distribution of asperity heights.
