Chrome is one of the most versatile plated metals in the industry. From the venerable “hard chrome” to the famous “decorative chrome”, no other plated metal has served so many needs for so many industries for so long. It has virtually no rivals. There is virtually no comparison to chrome. Chromium has excellent tarnish resistance, and the nickel undercoat in decorative chrome (Class 1) provides a good foundation for the lustrous chromium finish. The nickel also provides corrosion protection for the underlying steel. Another feature of chromium plating is that it resists cleaning chemicals, handling and abrasive wear.
Excellent hardness (RC-68-74), wear resistance and erosion resistance. It has low coefficient of friction and is resistant to heat. In addition to the above properties, it can be rendered porous for lubrication purposes. All coated steel parts having a hardness of Rockwell C 36 and higher shall be baked after plating at a minimum of 375°F ± 25°F per the following schedule:
Rockwell C36 Bake Schedule
Tensile Strength (Ksi) Time (at temperature hours)
221 & above 12
All Class 2 plated parts designed for unlimited life under dynamic loads shall be shot peened per MIL-S-13165 or MIL-R-81841 prior to plating.
Type 1: Bright
Type 2: Satin
Class 1: Corrosion protecting plating (.00001” minimum thickness on all visible surfaces)
Class 2: Engineering plating (.002 minimum thickness unless otherwise specified)
Class 2a: Plated to specified dimensions or processed to specified dimensions after plating.
Class 2b: Parts below Rc 40 and subject to static loads or designed for limited life under dynamic loads.
Class 2c: Parts below Rc 40 and designed for unlimited life under dynamic loads.
Class 2d: Parts have hardness of Rc 40 or above and subject to static loads or designed for limited life under dynamic loads.
Class 2e: Parts have hardness of Rc 40 or above and are designed for unlimited life under dynamic loads.