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Coating on stainless steel 4

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newstart18

Materials
Jun 14, 2010
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I am looking a coating/plating for stainless steel to add an extra layer of protection in a corrosive environment. The part is a 1/2 x 3/4 inch fitting, it is exposed to salt water and bleach, and the temperature exposed to gets to about 175 degrees F. I need to find a coating that is also abrasion resistant. I've never heard of coating stainless, but I guess the idea is that stainless can rust and the coating will add extra protection. If a little scratches/wears off, you still have the stainless beneath the coating. I suggested passivation, but they want the coating. If anyone has any ideas or suggestions to help me get started, I'd appreciate it. Thanks in advance.
 
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If you’re looking for both abrasion resistance and corrosion resistance, hard chrome electroplating or electroless nickel might work. Either one will change the dimensions of the fitting slightly (adds a few thousandths to the component), but it will be substantially more durable and resistant to corrosion. However, it’s hard to be more specific without seeing the part's configuration. Can you upload a print of the part?

Electro-Coatings
 
The material is SS430. I considered electroless nickel but the problem is that they also (of course) want something that doesn't cost a fortune. The thinking on nickel or chrome plating is they might as well just use iron (which they don't want to use) rather than stainless if the material will be electroplated or chrome plated. I think a powder coating that is fairly abrasion resistant and can handle temps to about 200F is what they have in mind. Is there a specific powder coat that would fit the bill?
 
There is a coating that we use that passes a 1000 Salt (NaCl) chamber test with excellent results. It is called Dacromet. It does increase the surface area, but does a great job on protection.
 
Ignore the post by Cervantis. Dacromet is a zinc flake coating used for ferritic steel parts. It will not help stainless steel for corrosion resistance, and it has poor abrasion resistance.
 
CoryPad is correct that for our application,we use it on mild steel parts, which was not part of your question. I only saw salt corrosion, and thought of this application. My appologies.
 
Hi, whilst not an extra coating electropolishing would increase its resistance to corrosion. I have used this in the marine industry to great effect. It has a chrome like apperance too.
On the downside it won't help at all with the abrasion.
I agree with you, my first pass would have been passivation.
 
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