The Fraunhofer IST offers a broad range of surface refinement possibilties. In addition to the specific configuration of the topography and coating using various methods, the institute chooses the optimum combination of various surface tretaments.
Defined configuration of the surface topography
The surface topography also influences the tribological properties. Smooth or structured surfaces are possible. The size of the sutrctures and the type of the shape or arrangement – random or determined – plays an important role for many applications. Especially in media-lubricated tribological systems the friction conditions can be improved considerably.
Diffusion treatment can considerably increase the wear resistance of steels and light metals. Depending on the base material, very thick hardening zones that do not chip off are created. With their supporting effect, steel and light metals provide an excellent basis for additional coatings deposited using the so-called duplex processes.
Diamond-like carbon coatings DLC
DLC coatings combine in an almost optimal way for excellent wear resistance with outstanding friction behavior. Additionally, other characteristics such as wettability can be selectively realized by integrating further chemical elements or by suitable process control.
Polycristalline diamond coatings
Polycristalline diamond coatings offer extreme wear resistance on cutting and precision grinding tools for working light metals, ceramics, or glass. Diamond coatings show excellent tribological characteristics and can therefore be used on highly stressed components.
Hard coatings (nitrides, carbides) are characterized hy high hardness and high temperature stability. They are particulary suited to serve as protective layers on highly stressed components. Boron-based coatings (e. g. BCN, TiBN, TiB2) show great potential for tool operations at high temperatures such as drilling, milling, thread cutting, extrusion, or die casting.
Ceramic coatings, in particular oxides auch as Al2O3, have a high degree of hardness, temperature stability and oxidation resistance. Therefore they offer, in combination with hard material layers, excellent protection in high-temperature applications.
Metallic coatings, pure metals, alloys or even dispersion coatings based on nickel or chromium are distinguished by a wide range of functionalities. Soft metals such as tin or silver are suitable as bearing materials. Metals such as gold, tantalum or stainless steels have excellent corrosion resistance. By installing particles or microcapsules, further functions, e. g. lubricants, can be integrated into the layers.