ANODIZE: An Acid finish used on
aluminum. Class 1 is a grayish yellow; Class 2 can be dyed a variety
of colors. It has excellent anti-corrosion properties and abrasion
BLACK OXIDE: This black matte
chemical finish adds no thickness to fasteners. It has minimal
corrosion resistance but can be coated with a preservative (usually
light wax) to further increase corrosion resistance. Can be used
on all metals as a decorative finish.
BRIDGHT DIP: Used on brass to enhance
its appearance. Does not add any physical properties other than
brightening the color.
CADMIUM: This non-porous metallic
plating is extremely durable in severe salt and humid environments.
Cad 1 is silver-grayish-white; Cad 2 has an additional chromate
coating either yellow-bronze or olive drab (dull olive) when specified.
Cadmium is very toxic - avoid contact with food or beverages.
CHROMIUM : This lustrous plating
leaves a beautiful mirror-like finish. It can be sued on most
metals for excellent corrosion resistance but is fairly expensive.
IRIDITE : A chemical conversion
coating for aluminum and aluminum alloys. Class 1 is gold color
and provides good corrosion resistance when left unpainted. When
used in conjunction with paint, it improves adhesion. Class 3
is a clear chemical film that provides corrosion resistance. It
should be used when low resistant electrical contacts are required.
NICKEL : This finish is good for
applications requiring a bright decorative appearance. Can be
used on steel, brass, copper alloys, and zinc alloys. It is magnetic,
has excellent wear resistance but is porous, and therefore has
less corrosion resistance than cadmium. Color is similar to stainless
steel but may be light, dull gray or almost white.
PASSIVATE : A nitric acid dip used
for stainless steel to remove the small metal particles that will
eventually begin to rust. By removing these chips, passivation
allows the stainless steel to naturally form a protective film.
Passivation does not change the color of the metal except to brighten
and bring out the shine.
SILVER : A decorative finish with
excellent rust resisting and anti-galling characteristics, especially
at high temperatures. It also has good electrical conductivity
qualities and therefore is often used in radio and electrical
applications. The main drawback of silver plating is high cost.
SOLID FILM LUBE : This finish is
also called "dry film lube". Usually for applications
when a conventional lubricant is difficult to apply or for applications
involving a sliding motion. This plating should be used when other
lubricants may be contaminated with dirt or dust. Parts plated
with solid film lube should be used within 12 months after application.
STAT (STATUARY) BRONZE : An electro
deposited layer of copper over steel with an oxidizing agent applied
to copper to blacken it. Mechanical burnishing obtains the antique
effect. As a final step an air-dried, clear protective coating
TIN : This plating can be electro
deposited or hot-dipped. The coloring is grayish-white. If a bright
finish is desired, specify "Bright Tin Dip". Tin provides
good corrosion resistance and meets the 24 hour 20% salt spray
tests. It can tolerate organic acids and therefore is well suited
to the food processing industry.
ZINC : A very popular plating which
seems to be replacing cadmium in many applications where toxicity
is a concern. It requires a thicker deposit to equal the corrosion
resistance of cadmium. Zinc 1 is called zinc clear with a bright
blueish0-white color. Zinc 2 has a chromate coating which adds
additional corrosion protection and a yellow tint. Black Zinc
can be used in applications requiring a black color with the need
for better corrosion resistance than Black Oxide provides.