Vapor Process
The mechanism of vapor phase deposition is similar to that of pack cementation. But components are out of the pack, not contacting with coating material. Coating material is composed of source metal and activator. Gaseous halide compound formed by reaction with source metal and activator is transferred to substrate surface by carrier gas such as argon or hydrogen. Coatings formed by vapor phase deposition are more clean than that of pack cementation without pack materials in the coating.
Advantage
- Low coating waste
- Uniform and clean coating microstructure without processing materials
Disadvantage
- Difficult to masking for non-coating area
