Chromium plating can be placed in two different categories:

1.     Engineering (Hard Chrome)

Engineering chrome can be used for corrosion protection, but is generally used when a thick deposit is needed to repair a part or for wear resistance. Examples of such parts are pistons, cylinders, aircraft engine parts, cutting tools, dies, oil tool parts and valves. Thicker deposits generally require machining after plating to achieve blueprint dimensions or surface finish requirements. Deposits may range from coverage to .030 inch. Hardness will range from Rockwell “C” 60-70.

Chromium has poor throwing power. Recessed areas such as holes or in corners of shoulders will have less thickness (or no thickness) then the majority of the part. Because of the poor throwing power of the bath, conforming anodes play a big part when plating chrome.

2.     Decorative

Decorative chrome is typically applied directly over bright nickel. The deposit is very thin usually ranging from coverage to 50 micro-inches. The coating function is to alter the color of the nickel to a more pleasing color preventing the oxidation of the nickel.

This coating, when put over bright nickel has a very bright, reflective surface. It is applied to a wide variety of parts ranging from washers to bumpers.  All surface defects are magnified with decorative chrome, so to achieve the “mirror” finish, the parts must be polished to a “mirror” finish prior to plating.

Decorative chrome generally is not plated directly on the base metal, but will be applied over the top of nickel. When this is done, it can be plated to many types of metals such as aluminum, zinc die cast, brass, copper, steel, and stainless steel.

Decorative finishes produced:

• Bright Chrome
• Satin Chrome
• Dull Chrome
• Duplex Chrome

Hohman Plating and Manufacturing, Inc.
814 Hillrose Avenue
Dayton, Ohio 45404
Phone: 937-228-2191
Fax: 937-228-5171

Copyright © 2007 Hohman Plating & Mfg., Inc. All rights reserved .