1. Field of application

As shown in figure 1 , which simulates unloaded contact between two portions of rough surfaces, the presence of microgeometries on the surface of parts can render contact discontinuous, especially when the microgeometries are large and not very deformable. Although microgeometries are characterized by small variations in height (fractions of a micron or even a few microns), we now know that they cannot be completely compressed under normal contact conditions. As a result, there are many phenomena that cause the contact behavior to be highly dependent on the microgeometry of the two surfaces under consideration