Hierarchical adaptive nanostructured PVD coatings for extreme tribological applications: the quest for nonequilibrium states and emergent behavior

摘要: Adaptive wear-resistant coatings produced by physical vapor deposition (PVD) are a relatively new generation of which attracting attention in the development nanostructured materials for extreme tribological applications. An excellent example such operating conditions is high performance machining hard-to-cut materials. The adaptive characteristics develop fully during interaction with severe environment. Modern could be regarded as hierarchical surface-engineered nanostructural They exhibit dynamic hierarchy on two major structural scales: (a) nanoscale surface layers protective tribofilms generated friction and (b) an underlying nano/microscaled layer. responsible some critical effects that strongly impact wear resistance coatings. A direction nanomaterial research discussed: compositional microstructural optimization dynamically regenerating nanoscaled friction. In this review we demonstrate correlation between microstructure, physical, chemical micromechanical properties hard their (adaptation) environment involvement complex natural processes associated self-organization Major mechanical coating, play significant role its properties, enhanced mass transfer, ability layer to provide dissipation accumulation frictional energy operation presented well. Strategies coating design enhance beneficial outlined. emergent behavior when improved features work whole. way, higher-ordered systems, they achieve multifunctionality under conditions.