How to identify that is really corrosion

[RubberDog]

Hello,

we have in our line some metal parts, that are produced overseas.
We use VCI and protective layers, but sometimes we still having corrosion (Iron Parts).
The problem is we apply an adhesive that was a rust color... So, sometime is hard to identify if what we see is really adhesive or corrosion.
I would like to know an analytical method to comprove that what we have is corrosion... Is this possible without IR or cristalography, etc?
Thanks for anyone who give me some ideas about the subject.

 

[rob768]

rust contains iron, whihch can be easily identified using spot tests. if your coating is non-iron, try something like a ferroxyltest fluid (sorry, don't know the compostion any more). This is a spot test used to identify free iron on stainless steel surfaces.

 

[EdStainless]

Maybe use a piece of tape to reach in and remove some surface material. If some material comes off then you have corrosion, or a coating that didn't stick.
It might be easier to check for the presence of the adhesive. Is there some filler or additive in the adhesive that would be easy to test for?

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