So I was thinking about corrosion and I came across this structure(see image)
Do you think the inner metal/alloy that is corroding is steel?
Also, what do you think the outer layer (in white) is? perhaps the metal is just coated with paint to avoid corrosion?
Finally, what type of corrosion do you think its undergoing? General Corrosion, Galvanic corrosion, uniform corrosion and so on.
Though a picture is not really enough information, approximate location at least and any simple tests on the materials shown would help a lot.
Its structural and ugly so its steel. Its mostly likely painted steel. I'd say the paint flaked off so it has general uniform corrosion. Why it looks black and not the regular red-brown is probably combination of oxides and sulphides formed as the corrosion products. I don't see a hint that its galvanised steel. Steel in exterior uses rarely suffers any corrosion other than general uniform corrosion.
