Additive Processes

Spray Coating

Spray coating is the application of liquid borne materials onto a surface.The sprayed material generallyhasi ormore of the following functions: filler, primer, colour, decoration and protection. High gloss, intense and colourful finishes are produced by a combination of meticulous surface preparation, basecoat and topcoat.
There are many different techniques used to apply decorative effects. For example, overlaying colours and tones using different spraying techniques will produce graduation, shading and mottling. Marbling is achieved by draping materials over a wet topcoat, which drags and smears it over the basecoat. Covering it with a clear topcoat seals in the pattern with dramatic effect.
Spray painting a Pioneer 300 light aircraft
Spray painting a Pioneer 300 light aircraft
Crackle varnish spray

Powder Coating

Powder coating is primarily used to protect the metalwork (aluminium and steel ) from corrosion and damage: the polymer forms a durable skin on the surface of the metal.It is a dry process that has low environmental impacts.

This dry finishing process is used to coat a range of metalwork by either electrostatic spray or a fluidized bed. The powder adheres to the workpiece electrostatically and is cured in an oven to produce a glossy protective coating. Read more.



Anodizing refers to a group of processes that are used to treat the surface of metals(aluminum, magnesium, and titanium.). The workpiece is made of the anode and submerged in an electrolytic solution. The process builds up the naturally occurring oxide layer on the surface of the metal. The film is hard, protective, and self-healing; aluminum oxide is inert and among the hardest materials known to man.

Anodizing has many benefits Including hardness, ease of maintenance, color stability, durability, heat resistance and corrosion resistance, and it is non-toxic。

Clariant Image Alu Finishing 2 2020


Electroplating is used to produce functional and decorative finishes on metals.Thin layers of metal, from less than 1 micron (0.000039 in.) up to 25 microns (0.0098 in) thick, are deposited on the surface of the workpiece in an electrochemical process.
Electroplating has many important functional roles, such as improved levels ofhygiene, ease of joining (such as silver and gold soldering) and improved thermal and electrical conductivity. Gold is used in critical applications to improve conductivity and ensure a tarnish free surface finish.
ABS Plastic Electroplating


Zinc and iron combine to produce a vety effective alloy that increases the life of steelwork and ironwork substantially. Unprotected metalwork continuously corrodes and its structure is undermined, whereas galvanized metalwork is protected from the elements and so retains its structural integrity.
This process can increase the life of steelwork to between 40 and 100 years. It is widely accepted that half of all new steel produced is used to replace corroded steel. Galvanizing dramatically increases the longevity of steel fabrications, reducing their environmental impact.
The roof of Waterloo Station in London was galvanized nearly 100 years ago. It has not needed re-galvanizing until recently.

Vacuum Metalizing

Vacuum Metalizing also known as physical vapor deposition (PVD) and sputtering, vacuum metalizing process is used to coat a wide range
of materials in metal to create the look and feel of anodized aluminum, chrome, gold, silver, and other metals.

This process combines a very high vacuum and an electrical discharge that vaporizes almost pure metal (most commonly aluminum) in a vacuum deposition chamber. The plume of vaporized metal condenses onto surfaces, coating them with a high-gloss film of metal.

Ceramic like Vacuum Deposition
Resources: Manufacturing Processes for Design Professionals by Rob Thompson