Evaluation of Adhesive Properties of Arc PVD Coatings on Non-Nitrided and Nitrided Various Substrates

This paper was designed to assess the adhesive properties of hard coatings made by physical vapor depositions on various substrates (AISI D2, AISI H-13 and M2) with and without an intermediate nitrided layer. An estimation of adhesion was carried out using the scratch test, where adhesion is measured by the critical load (Lc). This value was determined as the normal force affecting the indenter and causing the coating detachment as well as the acoustic emission signal containing the information on the extent of coating damage. The scratch track after the scratch test was also examined with an optical microscope to observe the failure modes of each coating. Hard coatings TiN, CrN and TiAlN were chosen for this study. Results of the test showed that harder substrates and coatings give higher values of critical loads.