Metallization of plastic parts (PVD)

Compelma proposes technologies for metallization of plastic parts, here is a presentation of the different PVD processes and of the machines.

Metallized plastics are used to replace metal objects by plastics with similar properties. Such as abrasion resistance and electric conductivity which are not innate characteristics of plastic. It also makes parts lower in weight and have higher corrosion resistance.

In general we use PEEK, PEI, ABS et PA plastics materials to process by vacuum metallization (Physical Vapor Deposition method ) to realize metal-plated parts. The PC, PET and PMMA are to avoid for metallization.

Materials:

The most common metal materials for surface treatment are:

Al ( Aluminum)
Cr ( Chromium)
Cu ( Copper Alloy)
Ni ( Nickel)
NiCu (Nickel Copper)
Sn (Tin)

What is PVD?

PVD is the abbreviation of Physical Vapor Deposition. It refers to the practice of using low-voltage and high-current arc discharge technology. It vaporizes the target material, and ionize both the evaporated material and gas under vacuum conditions.

By using the acceleration of electric field, the evaporated material and its reaction products are deposited on the part to be metallized.

PVD versus Traditional Electroplating

PVD coating and traditional electroplating are similar. Both belong to the category of surface treatment. Both are used to cover the surface of another material.

The difference between the two is that PVD coating film layer and the surface of the work-piece have:

higher adhesion
higher hardness of the film layer
better wear resistance and corrosion resistance
more stable performance than electroplating.

PVD coatings:

can be coated with a wider variety of films
can be plated out of a variety of more beautiful colors
does not produce toxic or polluting substances.

‍The characteristics of PVD coating

The PVD coatings are harder and have 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. PVD coating technology can achieve metallic like appearances on the surfaces of plastics

Durable surfaces

The surfaces metallized using PVD have the following characteristics:

abrasion resistance
scratch resistance
shedding resistance
cracking resistance
stable chemical performance
corrosion resistance
acid resistance
oxidation resistance

In the harsh environment such as sun or humidity:

the color doesn't change
no shedding or damage
stable performance
good cleaning - easy to remove paint and handwriting, no traces left.

Low cost

It reduces the time and cost required to clean and polish plated brass or gold.

The weight of the metallized part is lower than full metal parts, so it is easier to transport and to manufacture.

Excellent adhesion

It can bend over 90 degrees without cracking or peeling (PVD coating holds high adhesion and durability). Other technologies, including electroplating and spraying, cannot be compared.