nickel-plated aluminum
nickel-plated aluminum
(OP)
We build sensors of T6065 aluminum and have them nickel plated. One was returned from central Florida with many spots of white corrosion, which appear under a microscope to be growing from a small point where the plating may have been pitted. But since aluminum forms an oxide layer so quickly, and the oxide is not soluble, how can the aluminum be corroding even if the nickel plating has a pit? The device was outdoors in the rain/dew but salt should not have been present. http://f iles.engin eering.com /getfile.a spx?folder =08f41c5f- cdc4-4f27- 838f-3a86a d57d093&am p;file=cor rosion.JPG





RE: nickel-plated aluminum
RE: nickel-plated aluminum
RE: nickel-plated aluminum
RE: nickel-plated aluminum
Was the part wet constantly?
I would anticipate aluminum to acquire protective oxide film at nickel discontinuities, unless the part stays wet. Am I mistaken?
RE: nickel-plated aluminum
RE: nickel-plated aluminum
If the nickel is chips, or somehow exposes the aluminum. The aluminum then oxides (which is evident by the white marks).
Once the aluminum oxidizes, is that mark then stable? Or will it continue to pit deeper into the aluminum?
RE: nickel-plated aluminum
RE: nickel-plated aluminum
RE: nickel-plated aluminum
I've seen some other proprietary coatings out there that use an electroless nickle with teflon on aluminum that the teflon will actually self heal to the point that any surface defect will not propagate. I've seen these on Italian gearboxes, pretty sure it's from an Italian plater. The claims are legit though, we do a lot of destructive testing with chemicals, etc and can get most anything to fail. This stuff is as advertised though.
James Spisich
Design Engineer, CSWP
RE: nickel-plated aluminum
http://www.alumiplate.com/html/properties.html
RE: nickel-plated aluminum
RE: nickel-plated aluminum
The plating is pure aluminum that has an excellent anti-corrosion properties. Aluminum alloy will corrode without some kind of surface treatment. This is why in aircraft the use of clad aluminum sheets is common. The clad is a ~0.1 mm layer of pure aluminum on the sheet that protects the alloyed sheet.
RE: nickel-plated aluminum