Specializing in Conversion Coatings

AnodizingAluminum Finishing Services

Aluminum Anodizing

Available in clear & UV resistant Black

Anodizing of aluminum creates a thin, corrosion and wear resistant layer of aluminum oxide on the surface of the part. The layer will be scratch resistant, electrically insulation and increase corrosion protection.

The time in the etch batch can be varied to accomplish different surface finishes ranging from shiny to matte.

The anodized layer is grown on the aluminum in a sulfuric acid bath. The porous coating can be left clear or the porosity filled with a dye to color the coating. Following this process, the pores are sealed using a nickel containing seal.

Clear anodizing is typically done at a coating thickness of 0.6 to 1.2 mil. Since the anodizing process is consuming part of the base material to create the coating, the actual build-up is typically around 50%. So a 1.0 mil thick anodized coating will give about 0.5 mil of actual dimensional growth.

Offering Selection

Clear Anodizing
Black Anodizing
SS Passivation
Material used on
Stainless Steel
Coating thickness
0.2 – 0.8 mil
0.6 – 1.2 mil
0 – not measurable
0 – no coating buildup
Dimensional increase
~50% of coating thickness
~50% of coating thickness
Electrical conductivity
None, insulator
None, insulator
Type 3 – very good; Type 1A – good
No change from base material
MIL-A-8625F type II class 1
MIL-A-8625F type II class 2 (black)
MIL-DTL-5541 type II, class 1A and 3
AMS2700 method 2, ASTM-A967 citric 2
Gloss silver to matte silver
Medium gloss black to matte black
Slight yellow to blue tint to base material. Some light streaking possible
No change to base material – SS appearance
Corrosion resistance
Very good – 336 hour salt spray
Very good – 336 hour salt spray
Good – 100 hour salt spray
Excellent – no salt spray corrosion
ELV/WEE compliant
Cost of process
Max part size at WFL
30″ x 30″ x 48″
30″ x 30″ x 48″
30″ x 40″ x 108″
< 5" - bulk barrel

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