MIL-C-26074 Technical Information
With MIL-C-26704, there are a few key classifications an informed customer should understand.
- Grades – Thickness of Deposit
- Grade A (1000 microinches) – used for aluminum based alloys
- Grade B (500 microinches) – used for copper, nickel, cobalt, titanium, and beryllium
- Grade C (1500 microinches) – used for iron-based alloys
- Class Number – Processing Guidelines
- Class 1 – As plated, no subsequent heat treatment. A bake for hydrogen embrittlement relief is not considered a heat treatment.
- Class 2 – heat treated to obtain required hardness: May be used on all metals not affected by heating to 500 degrees Fahrenheit and above.
- Class 3 – Aluminum alloys nonheat-treatable, and beryllium alloys processed to improved adhesion of the nickel deposit.
- Class 4 – Aluminum alloys, heat-treatable, processed to improve adhesion of the nickel deposit.
Acceptable Base Metals:
Iron, copper, aluminum, nickel, cobalt, beryllium, titanium, and their respective alloys.
Strikes and Underplating:
Silver or copper plus silver may not be used as an underplate. When gold is applied to a copper rich surface such as brass, copper, bronze, or beryllium copper, an anti-diffusion underplate such as nickel shall be applied.