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How wet corrosion works
Hi there. I'm a high school student in garde 11 and I am doing an assignment on corrosion and finding it extremely difficult to understand and explain how wet corrosion works. I was wondering if oxidation actually involves the metal dissolving, as some information I have found has mentioned that it does so that the dissolved particles then react with the oxygen? I was also wondering why exactly steel rusts faster than pure iron does. and lastly why exactly does salt increase the rate of corrosion?
any help would be greatly appreciated.
student - Brisbane, Queensland, Australia
Corrosion NEEDS humidity, it NEEDS moisture ...t'other wise if it's dry, you shouldn't get any corrosion, eh?
Why does, you ask, iron corrode more quickly than steel ?
Surely that depends upon the 'ingredients', ie. the alloys in it .... ordinary iron has quite a higher Carbon content than steel and can possess some sulphur and phosphorus ... after all, steel is MADE from iron by a refining process (open hearth or electrical furnaces) to knock out the S and P and reduce the carbon content
Salt is an alkaline ... eg. seawater ... and that can eat up/reduce both steel and iron.
I hope that that helps.
- White Rock, British Columbia, Canada
(It is our sad duty to advise that Freeman passed away April 21, 2012. R.I.P. old friend).
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