• Evaporation 
• Sputtering 
• Arc Vaporization
• Chemical vapors and gases

2. The transfer of the vapor phase from source to substrate by -

• Line-of-sight 
• Molecular flow 
• Vapor ionization by creating a plasma 

3. Deposition and film growth on the substrate

These steps can be independent or superimposed on each other depending on the desired coating characteristics. The final result of the
coating/substrate composite is a function of each materials individual properties, the interaction of the materials and any process constraints that
may exist.

The selection criteria for determining the best method of PVD is dependent on several factors;

Physical vapor deposition is an evaporative coating process in which the basic mechanism is an atom by atom transfer of material from the solid
phase to the vapor phase and back to the solid phase, gradually building a film on the surface to be coated. PVD is a desirable alternative to
electroplating and possibly some painting applications because it generates less hazardous waste and uses less hazardous materials (i.e., no
plating baths).

The reduction of hazardous waste helps facilities meet the requirements of waste reduction under RCRA, 40 CFR 262, Appendix, and may also help facilities reduce their generator status and lessen the amount of regulations (i.e., recordkeeping, reporting, inspections, transportation, accumulation time, emergency prevention and preparedness, emergency response) they are required to comply with under RCRA, 40 CFR 262. In addition, since bath solutions are eliminated (i.e., less hazardous chemicals are used at the facility) there is less of a chance that the facility would meet any of the reporting thresholds for hazardous substances/chemicals under SARA Title III (40 CFR 300, 355, 370, and 372; and EO 12856). This technology also uses considerably less water than the traditional electroplating operations and as required under EO 12902, Energy Efficiency and Water Conservation at Federal Facilities. In addition, this type of system may require an air permit.

The compliance benefits listed here are only meant to be used as a general guideline and are not meant to be strictly interpreted. Actual compliance benefits will vary depending on the factors involved, e.g. the amount of workload involved.

PVD coating processes are compatible with most metals and some plastics either as coatings or as substrates. However, temperature constraints may limit the degree to which dense coatings can be deposited on some plastics. Finally, PVD processes do not normally produce the kind of coatings that work well where lubrication is required. Thus, PVD coatings are not usually good choices for parts such as fasteners.

The safety and health issues must be evaluated on a case-by-case basis. Consult your local Industrial Health specialist, your local health and
safety personnel, and the appropriate MSDS prior to implementing any of these technologies.

• The coatings are sometimes harder and more corrosion resistant than coatings applied by the electroplating process. Most coatings have high temperature and good impact strength, excellent abrasion resistance and are so durable that protective topcoats are almost never necessary. 
• Ability to utilize virtually any type of inorganic and some organic coating materials on an equally diverse group of substrates and surfaces using a wide variety of finishes. 
• More environmentally friendly than traditional coating processes such as electroplating and painting. 
• More than one technique can be used to deposit a given film.

• Specific technologies can impose constraints; for example, line-of-sight transfer makes coating annular shapes practically impossible.
• Some PVD technologies typically operate at very high temperatures and vacuums, requiring special attention by operating personnel. 
• Requires a cooling water system to dissipate large heat loads. 
• Selection of the best PVD technology may require some experience and/or experimentation. 
• High capital costs. 

Economic considerations are probably the primary hindrance to conversion of more plating operations to any of the vapor deposition processes. A rough estimate of the capital cost for a new vapor deposition installation is several hundred thousand dollars. Operating costs are, however, roughly equal to electroplating, although plating can be slightly less labor intensive.

Navy: Approval is controlled locally and should be implemented only after engineering approval has been granted. Major claimant approval is not required.

This is not meant to be a complete list, as there may be other suppliers of this type of equipment.