Tribological Properties And Wear Mechanism Of Hard Coatings

Abstract

In the modern technology tribologically suitable components and newlinedevices are important to increase the energy efficiency It is possible when newlineone can reduce the friction coefficient and wear of sliding components The newlineeconomic effectiveness can be achieved by better tribological system and newlinetherefore research in tribology is aimed at minimizing the energy losses newlineresulting from friction and wear In this view hard coatings deposited by newlinephysical vapor deposition PVD are adequate solutions for increasing the newlinework efficiency lifetime of tools and components newlineThe present thesis deals with hard tribological materials T Al and newlinecoatings such as TiAlN C N N N superlattice diamond like carbon DLC newlineand nanocrystalline diamond nanowire DNW films Various newlinecharacterization techniques were used to study morphology microstructure newlineand chemical state of the materials The thesis describes tribological newlineproperties of above mentioned hard coatings sliding against 100C 6 steel newlineAl O and SiC balls It also describes friction and wear based on classified newlinemechanisms and outlines material properties that influence the performance newlineof sliding surfaces Traditionally wear is associated with friction and wear newlinemechanisms are classified as adhesion abrasion erosion fatigue and newlineoxidational newlineMechanical and tribological properties of T Al alloy T AlN newlineC N carbon based coatings of DLC and nanocrystalline DNW were newlinereviewed The importance of such hard coatings and critical application in newlinemachine and industries are highlighted Moreover tribological properties and newlineevaluation of wear mechanism is introduced in the respect of microstructure newlineand chemical behavior of the sliding interfaces Various wear mechanism newlinewith different combination of sliding surfaces such as hard coating soft ball newlineand soft ball hard coating is reviewed in order to understand the wear newlinemechanism The fundamentals of some of the characterization techniques newlineused to study the mechanical tribological morphological structural and newlinechemical properties of the coating and wear track is introduced newline