Thread: Corroding steel

Hello all, I was wondering if I has a flat peice of steal or reinforced steel 1cm thick is there any chemicals I could pour on it and slowly it would start eating away at the steel and make it very weak so I could just hit it with a hammer and it would start breaking up?

I thought maybe nitric acid or sulphuric acid but I dont think these are powerful enough. Or if there are 2 or more chemicals I can mix that would then create a very corrosive liquid that would corrode the steel within say 1 week?

I think nitric acid is used actually, no idea how effective or over what time frame it might work though.

I have seen videos of it nitric acid corroding copper but copper is hardly a match for steel. Any chemicals that can be mixed that provide more corroding strength then nitric acid?

I've got no idea to be honest, but do a bit of research first if you haven't already. Steel might dissolve easily in nitric acid.

The only problem when nitric acid reacts with metal is that it lets of lots of smoke... not ideal really but there is nothing better is there?

I have been doing abit of research and nitric acid does not actually dissolve copper something else happens. Steel is mostly iron so i'm told and iron is sort of imune to nitric acid. I have found something better I think.

Pure anhydrous phosphoric acid is solid and colourless until it melts at 42.25 celcus, it turns into a viscous liquid. And when combined with Hydrochloric acid it produces a violet reaction possible of corroding even reinforced steel. Is this possible and/or have I got the chemicals wrong?

you could try trifloroethanoic acid, that rips everything to bits

Well I googled that acid and it came up with a spelling correction of Trifluoroethanol acid, is this what you ment or not? You say it rips everything to bits... even steel? And would would it be stored in if it rips everything to shreds? and when your pour it on something does it let of alot of smoke?

yehyeh, it's late at night but anyways
trifloroethanoic acid is strong because although it a carboxylic acid which is generally weak it has the negative inductive effect of the highly electronegative florine atoms. this takes the electrons away from the carbon in the COOH making the H more likely to dissociate and also making this acid stronger than mineral acids such as H2SO4, HNO3 and HCl.
I think they have to change the storage vessel after awhile but I can't remember.
this site has some nifty info http://www.jtbaker.com/msds/englishhtml/t5525.htm

It does not really say anything about its capabilities or anything but thanks for the link. It lists some precautions and stuff.

25% sulfuric acid will dissolve steel nicely, however it will be in solution as iron sulphate, it will never be in a state where it "breaks up" with a hammer though.

Originally Posted by uperkurk

Well I googled that acid and it came up with a spelling correction of Trifluoroethanol acid

The spelling correction is incorrect. Trifluoroethanoic acid is correct. It's an organic acid so it'll have the "oic" suffix. One could have trifluoroethanol, and I suppose it would even be acidic, but it's most likely not what you're looking at as the trifluoroethanoic acid would be stronger due to the presence of the carboxyl group (difference of a =O between it and trifluoroethanol).

Originally Posted by uperkurk

make it very weak so I could just hit it with a hammer and it would start breaking up

Another approach might be to embrittle it, i.e. make it harder than file or hacksaw steel so it'll shatter under (softer/tougher steel) hammer blow. Just torch it glowing hot and quench, repeat a few times. Mechanics do this sometimes.

Try Fluoroantimonic acid its 20 quintillion times stronger than 100% sulfuric acid.

http://en.wikipedia.org/wiki/Fluoroantimonic_acid

Acids will only dissolve the steel, only very high strength alloys are subject to hydrogen embrittlement anyway, has no effect on mild steel plate, even then all you may get is one crack. don't really see a goal for the initial question, you want to break up steel, is that it?

just super frezze it and hit it with hammer