ICMCTF2009 Session G7: Advances in Industrial PVD & CVD Deposition

The outstanding properties and advantages of crystalline CVD-diamond coatings applied onto high performance mechanical seals and electrodes are widely known. But similar to the diamond coating of tools an adopted coating set-up must be developed for industrial scale diamond coating of mechanical seals and electrodes. Mechanical seals ask for quite good flatness of sliding faces and electrodes require homogeneous, double side coating of large areas without bending or overheating of the metal substrate. For both applications different setups have been developed, by using the same platform, a CemeCon CC800/9.

For an economic industrial application a large filament array must be used to coat numerous or large parts in one batch. These filaments should perform long process times and must stand for several batch processes. Especially for coating of mechanical seals a horizontal setup assures the required flatness of the faces by providing homogeneous temperature distribution and gas composition over the complete coating area.

Since applications of diamond coated electrodes like waste water treatment usually need large coated areas and valuable substrate materials like Niobium, a double side coating of an electrode is preferred. The coating of such electrodes should be achieved in one batch without interrupting the process and turning the substrate. A vertical filament setup that is enclosing the electrode from both sides provides overall homogeneous distribution of doping elements (e.g. Boron), equal diamond quality and prevents bending at once.

We show that it is possible to coat with quite different setups different high performance products by using the same CVD-machine.

Cathodic arc evaporation process (AIP) is nowadays well established and widely adopted in many industries involved with thin film technology, mostly for triboligical applications such as cutting tools. As already well recognized, arc plasma is characterized by high degree of ionization ratio up to 90 % which assures superior adhesion and densification of the coating. High deposition rate is also an advantage of the cathodic arc compared to sputtering or other industrial PVD process for hard coating. Most recognized drawback is emission of macro-particles (MPs) which is considered more or less unavoidable nature of the cathodic arc process. Kobe steel has been a pioneer in realization of magnetically steered arc technology for industrial use and in this paper, a novel cathodic arc evaporation source based on magnetic steering principle and coating properties are reported. A magnetically arc evaporation source based on a new magnetic field design was developed and deposition of various hard coating, such as TiN, (Ti,Al)N, (Al,Cr)N and (Ti,Cr,Al)N was conducted in a industrial coating system. Surface roughness of standard 3 µm (Ti,Al)N coating from our previous two kinds of arc source is Ra=0.2µm for random arc and Ra=0.1µm for plasma enhanced cathode¹. Whereas the surface roughness can be as good as 0.02µm for 3 µm (Ti,Al)N coating deposited by the new arc source. Similar significant improvement in surface roughness can be observed for other major nitride coatings. The other characteristic of the coating deposited by the new source is significant reduction in residual stress. Residual stress of a few Gpa is commonly observed for arc deposited nitride coatings, whereas for the coatings deposited by the new source, the stress can be as small as 0.02GPa. A very thick (Ti,Al)N coating up to 20 µm can be grown on very sharp edge of a cutting tool without any chipping. Cutting test showed a significant enhancement in the tool life compared to a standard (Ti,Al)N coating with a few microns of thickness. Application of the new source to other coating systems will be reported.

¹K. Yamamoto, T. Sato, K. Takahara, K. Hanaguri, Surface and Coatings Technology 174 –175 (2003) 620–626.

The successful and innovative concept of Vacotec/Eifeler PVD technology based on the Alpha 400P coating system has been recently demonstrated¹.

These new Alpha 400/900P arc coaters show a broad variety of technical features to produce state of the art PVD coatings for industrial as well as R&D applications.

Highlighted are the flexibility for hard and lubricant coatings as well as the combination of in-situ plasma-nitriding with a hard coating. With these standard features of the new generation machines it is easy to create well adopted PVD coatings which are nicely fitting for many special applications.

Using the DC arc with very high plasma density offers the ability to produce films of high density and superb wear resistance features. This will be demonstrated with nanostructured AlTiN-based films and their properties.

Regarding the operating costs it is shown that the concept of multiple arc sources is a ve ry competitive way to produce high quality wear resistant films for industrial use. And the concept offers the possibility to produce PVD films out of up to 4 different cathode materials at a very high deposition rate.

A couple of applications concerning metal cutting, metal forming and component coating will demonstrate the broad flexibility of the presented PVD machine concept. Limitations of the concept and technology and some ideas how to overcome these will be discussed.

¹J. Anklam et al., ICMCTF 2008, G7-11.