A theory of rolling contact is presented which deviates from past theories in two respects: (a) the contacting surfaces are not assumed to be topographically smooth, and (b) Coulomb’s law of friction is replaced by a law describing the behavior of interfacial friction junctions. Numerical results for the slip as a function of the normal and tangential loads are shown to depend on a roughness parameter D, which, in turn, depends on surface topography, the gross geometry of the contacting bodies and on the normal load. It is found that when D is large (i.e., the surfaces are very rough, or the normal load is small), the slip-force relationship differs considerably from that predicted by the smooth-surface (or classical) theory. When D tends to zero, the two theories coincide. The dependence of D on topographical parameters is shown explicitly. Numerical examples indicate that for cylinders of small radius, surface-roughness effects may be important. Their importance decreases as the cylinder radius or the maximum contact pressure is increased, or the surface is made smoother.

This content is only available via PDF.
You do not currently have access to this content.