Comparison of nanostructure Comparison of nanostructure onto hot work tool steel substrate

Purpose: The aim of the paper was the investigation of the structure and the mechanical properties of the duplex TiN/(Ti,Al)N coating and the nanostructure TiAlN coating deposited by PVD technology onto hot work tool steel substrate. Design/methodology/approach: The surfaces’ topography and the structure of the PVD coatings were observed on the scanning electron microscopy. Diffraction and thin film structure were tested with the use of the transmission electron microscopy. The microhardness tests were made on the dynamic ultra-microhardness tester. Tests of the coatings’ adhesion to the substrate material were made using the scratch test. Findings: The duplex and nanostructure coatings demonstrate high hardness and very good adhesion. The critical load LC2 (coating delamination) lies within the range 80-85 N, depending on the coating type. It was found out that the duplex TiN/(Ti,Al)N coating show the best adhesion to the substrate material. Practical implications: The very good mechanical properties of the duplex and nanostructure PVD coatings make them suitable in industrial applications. Originality/value: The investigation results will provide useful information to applying the duplex and nanostructure PVD coatings for the improvement of mechanical properties of the hot work tool steels. The very hard and antiwear PVD coatings deposited onto hot work tool steel substrates are needed.