Effect of real contact geometry on adhesion

The effect of real contact geometry on adhesion was studied by measurement of pull-off force, real contact area, and real contact perimeter of fibrillar and dimpled flat surfaces. The structures, made of polyvinylsiloxane, were brought in contact with a flat glass substrate. These experiments demonstrate that adhesion does not correlate with the real contact area. The real contact perimeter is found to be the main geometrical factor governing adhesion. This results in a natural scaling effect with finer structures exhibiting stronger adhesion. (c) 2006 American Institute of Physics.