Coatings tribology -contact mechanisms and surface design

摘要

The fundamentals of coating tribology are presented by using a generalised holistic approach to thefriction and wear mechanisms of coated surfaces in dry sliding contacts. It is based on a classificationof the tribological contact process into macromechanical, micromechanical, nanomechanical andtribochemical contact mechanisms, and material transfer. The important influence of thin tribo- andtransfer layers formed during the sliding action is shown. Optimal surface design regarding bothfriction and wear can be achieved by new multilayer techniques which can provide properties such asreduced stresses, improved adhesion to the substrate, more flexible coatings and harder andsmoother surfaces. The differences between contact mechanisms in dry, water- and oil-lubricatedcontacts with coated surfaces is illustrated by experimental results from diamond-like coatings slidingagainst a steel and an alumina ball. The mechanisms of the formation of dry transfer layers,tribolayers and lubricated boundary and reaction films are discussed.