Nanostructured AlTiSiN/CrVN/ZrN coatings synthesized by cathodic arc deposition- mechanical properties and cutting performance

Abstract

Multicomponent and multilayer coatings have been attracting significant research interest, and these coatings allow the deposition of graded layers with a continuous variation of the concentration of the components to fulfill specific requirements at the substrate interface or that at the surface. On the basis of the binary compounds TiN, CrN and ZrN, various deposition strategies were developed to improve or adapt the hard coatings to a specific tribological problem. In this study, a cathodic arc deposition technology was used to deposit the AlTiSi/CrV/Zr and multilayer nitride coatings of AlTiSiN/CrVN/ZrN. By controlling the rotation speed of the substrate, hierarchical gradient and multilayered structures containing periodic AlTiSiN, CrVN and ZrN layers were found in the multilayer nitride coatings. Microstructure, mechanical properties and cutting applications were discussed. The highest hardness was obtained for the multilayered AlTiSiN/CrVN/ZrN coating with modulation period of 13.5 nm. The presence of multicomponent AlTiSiN/CrVN/ZrN with nanolayer structure mainly attributed to the formation of strong metal‑nitrogen bonding enhanced the hardness of the coatings. For the field test of cutting, a glass-reinforced epoxy laminate material was machined by the coated WC-Co end mills using a milling machine at high cutting spindle rotational speed of 40,000 rpm. The obtained results showed that the periodic thickness of the multilayer structure had a direct effect on the mechanical properties and cutting performance of the coatings. The design of nanostructured AlTiSiN/CrVN/ZrN hard coatings improved the overall tribological performance and showed applicability of these coatings in high speed cutting of glass-reinforced epoxy laminate materials.