Theory of rubber friction,contact mechanics,and the role of surface roughness on the adhesion of elastic solids

摘要

When rubber slides on a hard,rough substrate,the surface asperities of the substrate exert,oscillating forces on the rubber surface leading to energy "dissipation" via the internal friction of the rubber.I present a discussion of how the resulting friction force depends on the nature of the substrate surface roughness and on the sliding velocity,for both stationary and non-stationary sliding.I consider in detail the case when the substrate surface has a self affine fractal structure.I also present a theory for the area of real contact,both for stationary and sliding bodies,with elastic or elastoplastic properties.We also study the influence of surface roughness on the adhesion of elastic solids.Most real surfaces have roughness on many different length scales,and this fact is taken into account in our analysis.We consider the block-substrate pull-off force as a function of roughness,and find a partial detachment transition preceding a full detachment one.The theory is in good qualitative agreement with experimental data.