Alternatives to CrVI
Physical Vapor Deposition (PVD) is a method for producing metal-based hard coatings by means of generation of partially ionized metal vapor, its reaction with certain gases and by forming a thin film with a specified composition on the substrate. Most commonly used methods are sputtering and cathodic arc. In sputtering, the vapor is formed by a metal target being bombarded with energetic gas ions. Cathodic arc method uses repetitive vacuum arc discharges to strike the metal target and to evaporate the material.
All PVD processes are carried out under high vacuum conditions. The Ionbond PVD process is used for the deposition of coatings made of nitrides, carbides and carbonitrides of Ti, Cr, Zr and alloys like AlCr, AlTi, TiSi on a large range of tools and components. Applications include cutting and forming tools, mechanical components, medical devices and products that benefit from the hard and decorative features of the coatings. The typical process temperature for PVD coatings is between 250 and 450 °C. In some cases, Ionbond PVD coatings can be deposited at temperatures below 70 °C or up to 600 °C, depending on substrate materials and expected behavior in the application.
The coatings can be deposited as mono-, multi- and graded layers. The latest generation films are nano-structured and superlattice variations of multi-layered coatings, which provide enhanced properties. The coating structure can be tuned to producing the desired properties in terms of hardness, adhesion, friction etc. The final coating choice is determined by the demands of the application. The coating thickness ranges from 2 to 5 µm, but can be as thin as a few hundred nanometers or as thick as 15 or more µm. Substrate materials include steels, non-ferrous metals, tungsten carbides as well as pre-plated plastics. The suitability of the substrate material for PVD coating is limited only by its stability at the deposition temperature and electrical conductivity.