Deformation of Rough Surfaces in Point EHL Contacts

Abstract

The film thickness profile obtained by the optical interferometry technique merely represents a separation between contact surfaces and does not give the surface shape of contact surfaces. It has been pointed out that the actual shape of the surface roughness in rolling and/or sliding EHL contacts must be evaluated by separately obtaining the surface shape of contact bodies. The degree of the amplitude reduction in actual roughness depends on the mechanical properties of both contacting surfaces. That is, the deformation of roughness and the pressure at which roughness locates are controlled by the interrelationship between the rough surface and the mating surface caused by rolling and/or sliding motion. The method of finding surface profiles of both bodies separately and also the pressure distribution from the interferogram obtained by the optical interferometry technique is proposed in “Appendix”.