Friction and wear mechanisms of coated surfaces

The tribological mechanisms of coated surfaces are described using a generalised holistic approach to the friction and wear phenomena associated with coated surfaces in dry sliding contacts. This approach is based on a classification of the tribological contact process into macromechanical, micromechanical, nanophysical and tribochemical material transfer and contact mechanisms. The tribological mechanisms relating to new thin hard coatings with ultra-low friction are described. Optimal surface design regarding both friction and wear can be achieved by new multilayer techniques which can provide properties such as reduced stresses, improved adhesion to the substrate, more flexible coatings and harder and smoother surfaces.