Observation of Coating-Substrate Adhesion of Nanocomposite Hard Coating with Respect to the Deposition Parameters and Surface Finishing of Cemented Carbide Substrate

摘要

The paper deals with the issue of coating and surface finishing with edge preparation prior to the coating. Nanocomposite AlCrSiN hard coatings were deposited on WC-Co substrates with a negative substrate bias voltage in range of-80 to-120 V using cathodic arc evaporation system. The effect of variation in the bias voltage on the coating-substrate adhesion and nanohardness was investigated. The maximum nanohardness of coating was 37.7 ± 1.5 GPa with the good coating-substrate adhesion. Static Mercedes indentation test was performed on a Rockwell-type hardness tester. The indents were studied by scanning electron microscope to evaluate the coating-substrate adhesion. The H to E ratio that represents resistance to the plastic deformation was determined. The influence of surface roughness and time of used surface finishing methods on the coating-substrate adhesion was also investigated.