REVIEW OF MULTICOMPONENT AND MULTILAYER COATINGS FOR TRIBOLOGICAL APPLICATIONS

Improvement in performance of engineering components is achieved through the proper choice of materials, design, or both. Materials perform more efficiently even under severe working conditions when they are surface-engineered, i.e. coated and/or surface treated. Physical and chemical vapour deposition techniques have found increasingly wider use in such applications in recent years. The so-called first generation coatings (eg. TiN) are widely used in industrial applications, whereas adoption and implementation of second generation coatings (e.g. Ti (CN), (TiAl) N) are currently under serious consideration. The third generation of coatings - multicomponent and multilayer coating variants - are at the research stage. In this paper, the development of multicomponent and multilayer coatings for tribological applications are reviewed and the rationale behind the improved performance - established and anticipated - of such coatings is discussed.