-----
Rust formation on plated parts
Q. We manufacture speakers, and the outer frames & metal parts are zinc plated & passivated with yellow passivation.
What happens is after storing for a period of one to six months we find formation of rust. Plating thickness is 5 micron. Can any one suggest why this is happening and how we can prevent rust?
- Chennai, tamilNadu, India
2000
A. Two quick possibilities, Mr. Janadanan:
1. Plating shops are very corrosive atmospheres, being extremely humid as they are, and with so much acid mist (designed to strip zinc) about. If you are storing the parts in a plating shop, I'm not surprised that they are rusting.
2. The parts have to be dry . . . absolutely dry, or they will rust in storage.
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
(Ted is available for instant or longterm help)
2000
A. Aside from the "rust happens" truism, the plating thickness could be increased to give somewhat longer protection. Ten microns would be o.k.
Megan Pellenz
- Syracuse, New York
2000
Q. How rust is formed on plated components, i.e., parts plated with zinc nickel trivalent black passivation
V.Swamy Nathan- Chennai, Tamil Nadu, South India
September 15, 2013
A. Hi Swamy. I think we'd need a paragraph or two of details to be able to address your question. Short of that, Megan's "Rust happens" is applicable, i.e., there is rustable steel underneath the zinc-nickel plating.
Regards,
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
(Ted is available for instant or longterm help)
September 17, 2013
Q, A, or Comment on THIS thread -or- Start a NEW Thread