Anodized aluminum and nickel plated copper - potential corrosion

[YimKing]

I have an electrical part used in the aircraft (all weather and atmospheric condition). The part consists of (1) anodized Al 6061-T6 (2) anodized Al 2024-T3 (3) Cad plated CR steel. The anodizing is per MIL-A-8625 Type II. All the surfaces described above will be in contact with electroless nickel plated Copper (used as a ground strap). Will there be long term corrosion problem at each interface?

 

[hacksaw]

cadplated steel is the weak link, not the aluminum or the nickle plated copper. cadmium plating is poor in wet or condensing environments.

 

[aviat]

AC 43.13-1B Pages 11-71 – 11-81 covers this subject. It shows which washers to use with different combinations of materials, and different bonding jumpers. It minimizes the corrosion and parts likely to corrode will be the jumper or associated hardware. In other words they are sacrificed. Also covered are noncorrosive sealant conforming to MIL-S-8802 and means to measure resistance of jumpers.

Chapter 6 also has a lot of corrosion prevention info.