Adhesion of elastomeric surfaces structured with micro-dimples

•A mechanism to fabricate custom-tailored elastomeric adhesive systems is proposed.•The mechanism relies on dimple arrays having different dimple surface coverage and depth.•Suction phenomena are generated inside the dimples upon deformation.•Varying the dimple depth allow to tune the adhesion response of the surfaces.•The dimples act as crack-like defects at the edge of contact area. Topography has a dominant role in determining the adhesion properties of a surface. In this work we explore how arrays of micron-sized dimples can alter the adhesion performance of elastomeric surfaces. We study the effect of the dimple surface coverage, showing that the dimples act both as passive suction devices, allowing to exceed the adhesion performance of untextured surfaces, and crack-like defects, generating stress concentration at the edge of the contact area between the surface of the sample and a flat surface. Interestingly, our results reveal that the suction effect generated by the negative pressure produced by the dimples can be effectively tuned by adjusting their depth. These findings have significant relevance for the fabrication of adhesive systems in which selective adhesion to objects with small difference in weight is required.