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About PVD Coating
Physical Vapor Deposition (PVD) is a process to produce a metal vapor that can be deposited on electrically conductive materials as a thin highly adhered pure metal or alloy coating. The process is carried out in a vacuum chamber at high vacuum (10-6 torr) using a cathodic arc source.
Single or multi-layer coatings can be applied during the same process cycle. Additionally the metal vapor can be reacted with various gases to deposit Oxides, Nitrides, Carbides or Carbonitrides.
PVD Equipment
 Choosing the right equipment was the single most important decision in guaranteeing the success of the operation. Our first system was built in the USA and operates a patented Low Temperature Arc Vapor Deposition (LTAVD) process. This leading vacuum system manufacturer has 22 US patents and over 25 years of experience.
The second PVD system built in Europe utilizes the cathodic arc principles combined with multiple targets and has the ability to deposit different metals during the same coating cycle. Additionally this PVD chamber has an efficient handling system for quick transfer and loading of parts between cycles. Both manufacturers are recognized for producing the most sophisticated high volume decorative coaters in the world
This highly sophisticated equipment provides precise process control and easy to use computer graphic interface. These systems have the largest coating zones currently available in a batch coater so we can coat large complex shapes or large volumes of small components. The flexibility to coat a variety of substrate materials is extremely advantageous, particularly heat sensitive materials like plastic or zinc.
PVD Process
The parts to be coated are first cleaned. The cleaning process varies depending on the level of quality from the electroplater, substrate material and geometry. The parts are loaded into the vacuum chamber on custom fixtures designed to optimize the chamber load size and insure coating uniformity.
The vacuum chamber is evacuated to 10-6 torr (high vacuum) to remove any contaminants in the system. The vacuum chamber is backfilled with an inert gas argon and ionized, resulting in a glow discharge (plasma). This is the gas cleaning stage and prepares the parts for the initial metal deposition.
A high current, low voltage arc is initiated on the target (solid material used for deposition). The metal is evaporated and instantaneously ionized. These metal ions are accelerated at high energies into the vacuum through an inert gas or reactive gas and subsequently deposited on the part. The basic properties of the metal being evaporated (target) remain unchanged during the metal deposition cycle. Changing the volume of gas and type of gas during the reactive deposition cycle changes the nature of the coating producing ceramics like carbides, nitrides or oxides. For instance, zirconium nitride (ZrN) is a hard, yellow-gold colored coating with exceptional wear and corrosion resistance. Zirconium nitride has become predominant in the plumbing and door hardware industry as a lifetime brass color. Introducing measured amounts of nitrogen into the chamber during the zirconium deposition cycle produces zirconium nitride.
Chromium nitride is produced in much the same way. Simply by adding an additional gas such as acetylene (C2H2), you can create chromium carbonitride. This is a gray to black color.
The use and properties of the various coatings available from PVD coatings can, in many cases, be tailored to the individual customer application.
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