Structure and mechanical properties of TiCN-ZrCN multilayer coatings

Abstract

The present study is focused on the design, deposition and characterization of nanoscale multilayer TiCN/ZrCN coatings obtained by cathodic-arc PVD technique. The multilayer coatings with the bilayer period’s thickness of 12 nm, 20 nm and 32 nm were deposited on stainless steel and high-speed steel substrates at temperature of 320°C in a mixture of N2 and CH4 gases. Scanning electron microscopy equipped with energy dispersive x-ray spectroscopy, was employed to investigate the top surface morphology, cross-sectional morphology, bilayer thickness and structure of the coatings. Mechanical properties were investigated via Calotester, Nanoindentation tester, Scratch tester and Tribometer. The SEM/EDS cross-sectional analysis revealed a columnar morphology and well expressed multi-layered periodic structure. All the multilayer samples demonstrated an increase in hardness and well fracture resistance ability in comparison to TiCN and ZrCN monolayer coatings. The highest nanohardness of 41GPa and better wear resistance for the coatings with bilayer period of 12 nm was determined. The results of the study show that a reduction in the thickness of the individual sub-layers has a significant impact on the mechanical properties of the coatings.