Need to do Zinc Plating on Stainless Steel

A. Hi Wasim. As already noted on this page, getting zinc electroplating to adhere directly on stainless steel is unlikely because plating must be done onto raw metal and stainless steel almost instantly forms an oxide finish rather than leaving raw metal exposed. As described, the usual resolution to this issue is to do a Wood's Nickel Strike first ... this is a highly acidic solution which dissolves those oxides, and a dilute plating solution which simultaneously applies a thin nickel layer as the oxides are dissolved. After the nickel strike, you are plating onto nickel rather than onto stainless, so a number of different metals, including zinc, can be plated onto it. But it is difficult to go much further in the abstract -- please tell us the situation you have in mind.

Luck & Regards,

A. Although I can't think of an example of an item that is blue zinc plated on stainless steel, I know of no reason to think it is impossible or even particularly challenging on a technical basis. But plating onto stainless steel usually must start with a nickel strike to activate the surface anyway. The work would then need to go very quickly from this nickel strike tank to a zinc plating tank, and it may be logistically impractical on a production basis for many plating shops to quickly go from the nickel strike tank to the zinc plating tank if they are not set up for it.

Nickel is considered a decorative finish, more so than blue zinc, but is far better for conductivity as well. Zinc is never used for electrical conductivity because its corrosion products are sticky, voluminous, and non-conductive. The ideal decorative and conductive finish is gold plating, but that may be too expensive for the part in question, about which we'd like to hear more. Thanks!

A. I can't comment on whether you may have been fleeced based on your assessment that the finish is "quite dull" -- maybe the plater was trying to satisfy you with a dull nickel finish. But I can say that it doesn't need to be dull, and usually isn't in situations like this. The nickel plating can be quite bright.

But your plater is doing you a favor providing nickel plating rather than zinc plating :-)
It is very widely used for applications like this. Look at the charging contacts of your cordless phones, radios, DC adaptors, etc. ... these are often nickel plated, and certainly never zinc plated. Good luck.

A. Plating on 300 SS requires proper cleaning and acid activation followed by a Wood's nickel strike and then zinc plated. (requires appropriate rinses)

A. Hi JP. I'm not seeing why you should install stainless PEMs then have to nickel strike them in preparation for zinc plating when it seems you could just use steel PEMs and zinc plate the whole thing.

Luck & Regards,

A. Hi Somya. You need to start with a nickel strike process, then it can be done. Good luck.

Regards,

A. Hi Ravi,

To achieve good adhesion, steel parts shall be electro-activated by sodium hydrogensulphate/sodium bifluoride mixture follow by Wood's Nickel strike prior plating.

Regards,
David

A. Dear Ravi,

Please try the following process sequence.

1) Degreasing
2) Electrocleaning
3) Rinse
4) HCl Acid Activation
5) Woods Nickel strike
6) Rinse

Hope it will resolve your problem.

Note:
Please ensure where you are getting peel off problem, whether in Zinc Layer or Nickel Layer.

Thanking You,

A. Hi Danny. If the primary problem is galvanic corrosion, you can simply zinc plate the Be-Cu spring. A second approach would be to zinc plate a music wire spring, or you could try the uncoated stainless spring the supplier is suggesting; the galvanic corrosion should be greatly reduced compared to copper. But yes, you can zinc plate stainless steel after Wood's nickel striking it if that is the resolution ... but zinc is a poor contact material.

Luck & Regards,

A. Hi Eric. I don't think the plating process will actually hurt the spring, but non-adherent zinc plating will probably plate out onto it as ealier contributors noted,

Luck & Regards,