Physical Vapor Deposition (PVD) is characterized by the creation of a metal vapor that can be reacted with different gases to form a thin film coating. The most common PVD methods used today are arc deposition and sputtering. Both processes are carried out under high vacuum conditions within a coating chamber.
The typical process temperature for PVD coatings is between 250กใ C and 450กใ C, however in some cases PVD coatings can be deposited at temperatures below 70กใ C or up to 600กใ C, depending on the application or coating.
Items Typically Coated
The PVD process is capable of depositing coatings on a very large range of tools and components. Applications include cutting and forming tools, wear components, medical devices and decorative products.
Substrate materials range from steels and carbides to pre-plated plastics.
Coatings Typically Deposited
The coatings typically deposited are TiN, AlTiN, TiAlN, CrN, CrCN, TiCN and ZrN. More complex coatings can include TiAlCrYN or a W-C:H / DLC combination.
The coatings can be deposited as mono-layers, multi-layers, graded layers and the coating structures can be modified in terms of such properties as crystallographic orientation and nano-composite structure in order to produce the desired properties in terms of harness, elasticity, adhesion etc. The final coating choice is determined by the demands of the application.
Coating thicknesses typically range from 2 to 5 microns, but in some cases coatings can be as thin as a half micron or as thick as 15 or more microns.
The cycle time is determined by the load density, coating type and thickness. Typical cycle times range from 3-6 hours.
Advantages of the process:
Flexibility in terms of substrate materials and coating materials / combinations
Short cycle times / high productivity
The low to moderate coating temperatures means parts maintain their geometry and tolerances
The process is environmentally friendly