Twospoons
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Curious corrosion formation
We're carrying out salt fog corrosion tests at work, and one of the test pieces has produced these weird little tubes, like little trumpets about 2mm
in diameter. The substrate is zinc plated steel, and the little tubes grew over several days during the rest phase - that is out of the fog chamber
and sitting on the bench at room temperature. Humidity here sits around the 60-70% mark.
Anyway, I just thought they were interesting.
Helicopter: "helico" -> spiral, "pter" -> with wings
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Daffodile
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Kill it with fire before it lays eggs?
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BromicAcid
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That is pretty awesome, thanks for sharing.
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deltaH
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Spectacular!
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NeonPulse
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That is pretty cool. Any ideas on how they formed such strange shapes?
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wg48
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Those forms are super awesome.
I have seen bubbles of corrosion products (rust) on steel. Possibly caused by a blob of condensation initially forming then insoluble corrosion
products deposited at the surface of the blob.
Perhaps in your case the corrosion products are deposited at the edge of the blob forming a ring. As the ring grows it forms a tube or trumpet if the
diameter increases with growth.
The floor of my shed tends to be cold (possible a little damp too) steel objects left on the floor sometimes develops those bubbles of rust. But they
occurs in just a few points on the steel. Possibly where a protective coating fails. Perhaps the initial corrosion products are deliquescent so an
initially microscopic spot grows while the rest of the steel remains free of condensation. I will have to check for trumpet forms now.
I suggest you save some specimens of your steel and documents the conditions. Can you take a time lapse video of the growth? You could post it on
Youtube with a provocative title along the lines of a metal eating fungi LOL.
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Morgan
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They might be called tubercles.
http://ecscorrosion.com/galvanized-pipe-vs-black-steel/
[Edited on 10-3-2016 by Morgan]
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