The fundamentals of coatings tribology are presented using a generalised holistic approach to the friction and wear mechanisms of coated surfaces in dry sliding contacts. It is based on a classification of the tribological contact process into macromechanical, micromechanical, nanomechanical, and tribochemical contact mechanisms and material transfer. The important influence of thin tribo-and transfer layers formed during the sliding action is shown. 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 substrated, more flexible coatings and harder and somoother surfaces. The differences in contact mechanisms in dry, water-and oil-lubricated contacts with coated surfaces are illustrated by experimental results from daimond-like caron coatings sliding against a steel and an aluminal ball. The mechanisms of the formation of dry transfer layers, tribo-layers and lubricated boundary and reaction films are discuessed.
展开▼
