electroless nickel plating not possible on certain alloys? 1

[rhmeng]

I was sitting in a review and someone mentioned that certain alloys are unable to be electroless nickel plated. I did some research and was unable to find anything about alloys not being able to be plated. Does anyone know if/why there are alloys incapable of being electroless nickel plated? Thanks

 

[tbuelna]

Are there some specific metal alloys that you have in mind? There are many metal alloys that you would not have any practical reason to apply electroless nickel plating on. So it would be very helpful if you could limit the range of metal alloys being considered.

 

[CoryPad]

Electroless nickel has poor adhesion to alloys containing significant amounts of lead, tin, cadmium and zinc. Usually a copper strike plating is applied to these materials before plating.

Other alloys may not be suitable with electroless nickel plating due to the high temperature aging (> 300 [°]C) and the resultant distortion, reduction of mechanical properties and/or damage. Examples here would include high pressure die cast aluminium alloys.

 

[rhmeng]

From the conversation it sounded like they were talking about aluminum. I understand that you would not need to electroless plate several alloys, but am looking to find what you cannot plate. I did not think about the temperature aspect of the materials, it is a good point @CoryPad.

 

[swall]

Electroless nickel over aluminum poses issues of galvanic corrosion. I have seen 6061 aluminum with electroless nickel develop severe pinholing due to galvanic corrosion.

 

[rhmeng]

i thought that was only an issue when there is some sort of conductive substance between the two materials? It will corrode just in atmosphere?

 

[tbuelna]

EN can be applied to aluminum, but it requires a specific process. EN is commonly applied to aluminum electrical hardware such as connector bodies or housings, because it is durable, conductive and corrosion resistant.