Wasnt sure where to post this one as it isnt directly related to my other WIP and its asking help before ive even started a project.
There is a 1600 year old pure iron pillar called today The Dehli Iron Pillar in india that defies history as we know it because it should have disintigrated long ago because iron rusts, right?
Wrong.
Iron with impurities in it rusts, pure iron does not, but seeing as it is virtually impossible (not toatally) with todays technology to create perfect iron with no impurities how was a pillar made around 400AD of such pure iron that 1600 years later it has almost no rust.
Its a very important object and something im looking to do a project on (pillars are easy :)) but good refrence pictures of this pillar are hard to come by.
This is where YOU come in and as replies to this sort of thread usially come to nothing i thought i would put out a cry for help with plenty of time to spare before i have to begin this.
Simple: it wasn’t made of pure iron. Iron things disintigrate over time not because they rust, but because the rust flakes off, exposing more iron to further oxidation. These Indian ironmongers seem to have discovered the principle behind what today is called cor-ten steel, it’s basically an iron alloy that forms a tightly bonded layer of oxidation. Since the layer doesn’t flake off, it protects the metal underneath from further deterioration. I’m not saying it’s any less a technological tour-de-force, though, cor-ten is not easy to make, either.
