Contact between Fractal Rough Surfaces

The contact behaviors between two rough surfaces are vital to the study of contact pitting and surface scuffing failures. The fractal rough surfaces with anisotropic textures are simulated based on Weierstrass-Mandelbrot function. The contact between two rough surfaces is analyzed based on elastic and elastic-plastic contact models. The numerical results of elastic model show that the contact pressure distribution between rough surfaces is extremely ununiformed; that the real contact area is just a small part of the nominal contact area; and that the maximum value of von Mises stress and its location are also significantly affected by the surface topography of rough surfaces. Furthermore, the plastic deformation of surface asperities is considered with the elastic-plastic contact model for contact between two rough surfaces. Results of the elastic and plastic model demonstrate that the real contact area has significantly increased compared with the elastic contact model; and that the contact of surface asperities exhibits both elastic and plastic behavior under light load, while completely plastic under heavy load.