Wie Nanostrukturierung die Grenzen der Hartstoffbeschichtung erweitert: Dicke Hartstoffschichten, hergestellt mit einer PVD-Dünnschichttechnik
How nanostructuring extends the scope of hard materials: Thick hard coatings applied using PVD thin film technology
Hard material coatings have been used for decades to protect tools and components from wear. Using PVD or CVD processes, metal nitrides, oxides, carbides, or amorphous carbon coatings can be formed, all significantly harder than tool steel or hard metals. Typical thickness of such coatings is up to 10 mm. Formation of such coatings on the industrial scale is now an established technology although deposition of thicker coatings (>> 10 mm) using PVD is more challenging. In addition to problems arising from internal stress in such deposits, the thicker coatings often exhibit inhomogeneous structures, typically caused by growth defects or occluded particles. Formation of such defects or at least, inhibiting their propagation, must be prevented as far as possible during the coating process. This can be achieved for example, by using a special layer design on the nanometre scale. Using experimental results, some aspects of this approach are described in detail.