Intricate Mechanisms Raising and Lowering Adhesion

MORE INTRICATE MECHANISMS RAISING AND LOWERING ADHESION 

Those Particles receding from one another with the greatest Force, and being most difficultly brought together, which upon 

Contact cohere most strongly Isaac Newton, Opticks, p. 396 

Obviously, roughness is a barrier which inhibits molecular contact and strong adhesion between surfaces. But more significantly, the roughness does not usually deform elastically as the surfaces make contact, as shown in Fig. 8.2. 

Another roughness-dependent mechanism for adhesion hysteresis can be seen in humid atmospheres. As the rough surfaces are brought together, the 

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