Sciencemadness Discussion Board

non noble corrosion resistant metal and alloys for storing or reacting corrosive chemicals

nikotyna1919 - 20-6-2020 at 16:25

what kinds of non noble metals and alloys is corrosion resistant for storing or reacting halogens,corrosive gases mineral acids and salts in any concentration at room temperature like hydrogen chloride gas, nitrogen dioxide gas, sulfur trioxide gas, hydrobromic acid, hydrochloric acid, hydroiodic acid, nitric acid, sulfuric acid, phosphoric acid, ammonium chloride, copper chloride, ferrous chloride, stannous chloride




[Edited on 21-6-2020 by nikotyna1919]

[Edited on 21-6-2020 by nikotyna1919]

are alloys more corrosion resistant than pure metals

nikotyna1919 - 20-6-2020 at 16:38

i want to know which is better alloy or pure metals in corrosive environments

j_sum1 - 20-6-2020 at 16:56

Depends. Both on the specifics of the metal and also the environment where corrosion is occurring.

Stainless steel is obviously an alloy of steel and manufactured to prevent corrosion. But in a salty water environment, some grades of SS will actually corrode worse than mild steel: often because they corrode via a different mechanism.

Concentrated sulfuric acid is routinely transported by rail in large vessels of low alloy steel. You might anticipate a very corrosive environment but the rate is slow and predictable. But many steel alloys would not hold up as well.

Aluminium and aluminium alloys resist corrosion well. But that is due to the protective surface oxide coating that develops on Al. If you have an alloy that alters the interatomic spacing sufficiently such that the oxide does not adhere as well then you will have something that corrodes rapidly. Likewise if you have Hg or Ga present then this weakens the metal by diffusing through the grain boundaries as well as into the bulk metal. Technically, an alloy is formed and it has inferior structural properties to the original metal. Including the fact that it is subject to rapid oxidation along the now-exposed grain boundaries.

So... depends on context. What metal? What alloy? What environment?

cyanureeves - 20-6-2020 at 17:01

brass is more resistant than tin probably but i doubt it beats copper.

j_sum1 - 20-6-2020 at 17:27

Quote: Originally posted by cyanureeves  
brass is more resistant than tin probably but i doubt it beats copper.

Brass is more resistant than zinc. I don't think tin is a valid comparison.

And, in all honesty, it would not surprise me if brass excelled copper in normal outdoor environments. Compare a brass tap with copper sheet roof... The latter can become quite green.

But I think bronze probably weathers better than copper: hence its use in statues.

mackolol - 21-6-2020 at 02:44

Chromium is very resistant. All chemical resistant alloys consist of chromium, but I don't know exactly which one of mentioned by you chemicals can be stored in such containers.