| Finish |
Color |
For Use On
(Material) |
Corrosion
Resistance |
Characteristics |
Zinc
(Electroplated) |
White to Blue Grey |
All Metals |
Good |
Most common used plating. Good rust-resisting qualities. |
Cadmium
(Electroplated) |
Bright or Silver Grey |
All Metals |
Excellent |
Superior rust-resisting qualities used in marine & aviation. |
| Chromate |
Yellow, Olive drab,
Black, Blue/White |
Zinc & Cadmium Plated Parts |
Very Good |
A secondary dipping process after plating increasing corrosion resistance. |
| Dichromate |
Yellow, Brown, Green |
Zinc & Cadmium |
Very Good |
Secondary dip same as chromate only with a rainbow appearance. |
| Black Zinc |
Black |
All Metals |
Very Good |
Shining black appearance with rust-resisting qualities. |
| Black Oxide |
Black |
Ferrous Metals |
Fair |
Chemical discoloration; combined w/an oil dip. Rust resistance comes from the oil only. |
| Phosphate & Oil |
Charcoal Grey or Black |
Steel |
Good |
Zinc or manganese phosphate used with a rust-inhibiting oil dip. |
| Color Phosphate |
Blue, Green, Red, etc. |
Steel |
Very Good |
Chemically produced coating superior to regular phosphate and oil. |
| Iridite |
Olive drab, Green, Black, Red, Blue, Bronze |
All Metals |
Good |
Applied on top of zinc or cadmium plating as a die for color. |
| Nickel |
Silver |
All Metals |
Very Good |
Hard Stable Finish. |
| Chromium |
Bright Blue/White |
All Metals |
Very Good |
Hard lustrous finish adds wear resistance. |
Hot Dip Zinc
(Galvanizing) |
Dull Grey |
All Metals |
Very Good |
Maximum corrosion protection. |
| Passivating |
Bright - Etched |
Stainless Steel |
Excellent |
Parts are dipped in nitric acid which removes iron particles & brightens the finish. Produces a passive corrosion-resistant finish. |
| Anodizing |
Frosty - Etched |
Aluminum |
Excellent |
Acid dip produces a hard oxide surface. |
