What's the difference between thermal evaporation and sputtering?
Thermal evaporation is a process where you heat the metal to be deposited (usually aluminum) in a vacuum chamber until it melts and then boils-off as a vapor. There are different ways to heat the aluminum, but a tungsten filament is the most common. The vapor condenses onto all surfaces in the vacuum chamber forming a thin film. Thermal evaporation is the process most traditional vacuum metalizing suppliers use.
Sputtering, on the other hand, is a plasma-based process whereby the metal to be deposited is bombarded by high energy ions, which causes atoms of the metal to be knocked off, or sputtered, from the surface. These atoms condense on the part surfaces inside the vacuum chamber, forming a thin film. The advantages of sputtering include 1) precise control of deposition rates and thickness; 2) compatibility with nearly all metals, including metal alloys.
How thin are the layers applied during the vacuum metalizing process?
Shielding films are typically 1-2 microns thick.
Reflective films are typically .05 - .1 microns thick.
Decorative films can be from .02 - .1 microns thick.
VTI has two automatic conveyor-based UV-cure robotic spray paint lines. We can topcoat after metalizing if the required abrasion resistance for the metalized parts are severe.
What size items do you accept for vacuum metallization?
The maximum part size that will fit the vacuum chamber is 28” wide by 48” tall.
The maximum part size that can be painted is 16 “ wide by 20” tall.
Are there any materials you can’t coat?
There are certain plastics which are very difficult to coat and get good adhesion. Polypropylene is the most problematic.
How long is the turnaround time for a project?
A typical job takes about 2-3 weeks to get into our production schedule. The time for production depends on the number of pieces that need to be coated.
What are your minimum and maximum order sizes?
We are structured primarily for higher-volume jobs. We do not accept “one-off” jobs, nor very low-volume work. Annual production value should be in the $10,000 range and above. We have no maximum order size.