Will zinc plated bolt on steel plate corrode? 3

[TJK1]

Is it O.K. to have a yellow zinc plated bolt with washer and nut, fastened to a very large plain carbon steel floor plate? Would it be better to use a stainless steel bolt? Would a silver colored zinc plating on the bolt be better? Does the yellow zinc and silver colored zinc offer the same degree of corrosion protection?

 

[Metalguy]

Any zinc coating will slowly dissolve as it sacrifically protects the steel right next to it. After a while you'll have an unplated bolt. That may or may not be a problem for you. Can you use a "good paint/coating" to protect the area?

 

[CoryPad]

It is common practice to use zinc plated fasteners with uncoated steel parts. It would be a better practice to coat the panel also. If you use a stainless bolt, the carbon steel panel will corrode preferentially, which may or may not be a good thing. Yellow chromate conversion coatings are thicker and much more corrosion resistant than clear chromate (what you call silver colored zinc).

Regards,

Cory

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[sawhney]

I think if your application is not having any corrosice chemical over there than there's no need to go for nay of the Zn coating.In case of virgin application SS will be bale to take care of nay of the corrosion problem,it is meant for.Othrwise first give the data of the environment.