Nickel Plating There is a nickel finish for almost any need. Nickel can be deposited soft or hard - dull or bright, depending on process used and conditions employed in plating. Thus, hardness can range from 150 - 500 Vickers. Can be similar to stainless steel in color, or can be a dull grey or light grey (almost white) color. Corrosion resistance is a function of thickness. Has a low coefficient of thermal expansion. Is magnetic. All steel parts having a hardness of Rc- 40 or greater require a post bake at 375º+ 25º F for 3 hours. This specification has superceded the QQ-N-290 specification.
Spec.	Thickness	Comment
AMS-QQ-N-290		Note: All steel parts having a tensile strength of 220,000 or greater shall not be nickel plated without specific approval of procuring agency.
Class 1		For corrosion protection. With typical 0.0002" copper undercoating prior to the nickel plate.
Grade A	0.0016" min.
Grade B	0.0012" min.
Grade C	0.0010" min.
Grade D	0.0008" min.
Grade E	0.0006" min.
Grade F	0.0004" min.
Grade G	0.0002" min.
Class 2	0.002" min. unless otherwise specified	For engineering applications.