Anti-corrosion surface treatment

Simulation Generality
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1

Hello
I have an order for supports that will fix the exterior in sheet metal 10/10I want to know and what I can cut the cold-rolled steel sheet supports then do the zinc coating treatment and finally do the epoxy painting... In this case, do I guarantee the anti-corrosion of the supports that will be fixed outdoors...
Regards 

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Hello

We are required to make this kind of piece in our workshops. For my part, this is the process we use. Afterwards, you can use a galvanized + powder coating sheet.

3

Hello

The problem with galvanized sheet metal is that after laser cutting the edges became a vulnerable point for corrosion  

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Yes, you're right if laser cut. Otherwise, guillotine cutting no particular worries.

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Hello
Yes, you can and it's the best way to do it.

On the other hand, I am less sure of the usefulness of zinc plating as an intermediate operation.

In general, the parts are sanded before epoxy paint for a good adhesion and that's enough (Caterpillar does it like this, among other things!). Especially since epoxy does not hold as well on a galvanized surface because the paint tends to de-laminate due to a lack of adhesion, without this altering the galvanized layer.

What is especially important is the atmosphere in which the pieces are displayed. Ordinary weather or a hard, permanent saline atmosphere (such as on a boat at sea) and moderate saline exposure (house by the sea). Also specify whether they are passive supports, fixed such as cable or structural supports, or active supports, subject to movements or snags, repeated stalls.

However, ask the company that will do the surface treatment which will confirm or deny my words because there are now plasma treatments that give very good results for corrosion.

Kind regards

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Hello

The brackets are fixing clips for a ventilated façade (with stoneware slabs), in a saline  atmosphere of 1000 pieces ... If this is the case I will do the zinc coating and then the epoxy paint, and I hope it goes well ...

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Hello

If it's in a saline atmosphere, you should almost take 316 stainless steel because the salt will eat everything...

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@ac cobra

You are absolutely right because if you take the price difference between steel with two surface treatments, plus all that this implies in logistics and administrative costs, compared to the stainless steel part, there is no possible comparison stainless steel is cheaper.

In addition, sandstone slabs playing pigeon fly from the top of the façade, it makes a mess, especially if it causes a death.

I have the impression that our opinion doesn't count since the poster says this { If this is the case I will do the zinc coating and then the epoxy painting, and I hope it goes well }

I don't know what you think but burning a candle in St Rita, patron saint of desperate causes, is less effective than 316 stainless steel.

It's going well should not be confused with it's going well ;-)

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In our country, if there is a risk of corrosion, we systematically use 316L. As Zozo_mp explains, in terms of value for money, it's the best.

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That's why I proposed it too, you'll have to see exactly what you need because there are different types of 316 stainless steel: 316 (≤ 0.07 carbon content);  316L (" L " stands for, " low carbon " ≤0.03 carbon content) and also 316Ti (with titanium). Type 316 alloys offer better resistance to general corrosion and pitting or crevice corrosion than conventional austenitic  chromium-nickel stainless steels, such as Type 304.

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A tip too

Make bend radii as large as possible (when possible) based on design constraints.

This avoids micro-folding cracks which are nests of corrosion.

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Hello 

Thank you for your interaction... and I want things to go well and prove that I'm here and I ask people to experience ... And my words that I wrote as a conclusion to the words of the members... and probably I'll make stainless steel... But I hope you can answer, can I paint on stainless steel? 

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Of course it is possible to paint stainless steel, you can apply any surface treatment to it...

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If it's only for a support, there is also the corten which is nice. It is a material that rusts superficially and therefore also protects itself with a very good resistance over time.