Prediction of the Coating Durability Under Oscillating Sliding Contact: Introduction of a Local Energy Density Parameter

The knowledge of wear kinetics of thin soft lubricant or hard coatings under alternated sliding contact is of great interest for many industrial applications. Because the coating endurance is related to the substrate reaching condition, it has been shown that classical wear volume descriptions are not appropriated. A local damage description, based on a local friction dissipated energy density variable is then introduced. It consists to compare the coating endurance (i.e. number of sliding cycles) versus the maximum local energy density dissipated through the interface per sliding cycle. A “life time vs maximum dissipated energy density master curve” is obtained and rationalized through a parabolic evolution. The coating endurance is modelized through a simple ratio between an energy capacity variable, representative of the durability of the studied coating. Applied to hard coatings (TiN) the stability of this approach has been confirmed for solid lubricant coatings.