On the Effect of a Rate-Dependent Work of Adhesion in the Detachment of a Dimpled Surface

Patterned surfaces have proven to be a valuable design enhance adhesion, increasing hysteresis and the detachment stress at pull-off. To obtain high adhesive performance, soft materials are commonly, used, which easily conform countersurface, such as polymers elastomers. Such viscoelastic; i.e., they show rate-dependent properties. Here, of two half spaces is studied, one being flat other having dimple in limit short range adhesion power law work observed by several authors. Literature results suggested that dimpled surface would pressure-sensitive showing possible adhered states, weak, partial contact, strong when full contact achieved. By accounting for “weak state” may much stronger than it was purely elastic case, hence interface more tough separate. We study pull-off surface, weakly depends on preload, but strongly affected dimensionless unloading rate. Finally, implications presented from rough substrates discussed.