Investigations of mechanical and tribological properties of CrAlN+C thin coatings deposited on cutting tools

Abstract

Physical vapor deposition (PVD) of hard coatings such as titanium nitride have been used in industry reality since the beginning of the 1980s. Two processes, Arc-Ion plating (AIP) and Magnetron-sputtering-ion plating (MSIP), were responsible for the early commercial success of hard coatings on high speed steel tooling. There are many similarities and differences between these two PVD hard coating processes, but not all of the commonly used PVD hard coatings can be well deposited with the two systems. In this paper, CrAlN+C thin coatings were deposited on cutting tools materials using a new Physical Vapour Deposition (PVD) hybrid process. The hybrid process is a combination of random Arc-Ion-Plating (AIP) and balanced Magnetron-Sputter-Ion-Plating (MSIP) process, where both processes work simultaneously. The cutting tools should possess the following mechanical and tribological properties: hardness, adhesion, low coefficient of friction and good bond strength between coating and substrate. Coatings that were deposited with the PVD hybrid process showed the required properties for cutting tools. From the machining test results (made from the IPT Institute in Dresden) we can conclude that the CrAlN+C/C coatings can be applied in machining industry. The present work was an advanced AIF-project.