Scientific name for rust?
Scientific name for rust?
(OP)
What is the scientific name for rust or corrosion? How do you explain the delaminating of a steel beam that has been exposed to moisture. I need to talk to a group of kids about this, and I just don't want to say it rusted. PS this is totally out of my field, but have been asked to do this as a "knowledgeable person".





RE: Scientific name for rust?
RE: Scientific name for rust?
Very simple.
What you are describing as layers peeling off are layers of Magnetite (Fe3O4). Magnetite isn't a true compound but a mixture of FeO and Fe2O3. Magnetite can be very dense, closely approaching the density of iron. As it reverts to the more stable forms of iron oxide the volume of the scale increases thus the appearance of delaminating.
What you are describing is very common in splash zones especially around salt water. That is why the Navy was always chipping and painting.
You need to look up Magnetite.
RE: Scientific name for rust?
The usual mechanism is oxidation, iron turning into iron oxide (rust). This causes failure for a number of reasons. The loss of metal makes part thinner and they might not be able to carry the load. The corrosion products take up more volume than the metal did. This swelling effect can pry points loose, cause splitting (rusting re-bar in concrete), and even break metal parts.
The other thing that happens is that once corrosion starts it often causes more water to get trapped which accelerates the process.
There are some good corrosion overview presentations available at www.nace.org
= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection
http://www.trent-tube.com/contact/Tech_Assist.cfm
RE: Scientific name for rust?
http://en.wikipedia.org/wiki/Rust
In describing the condition (corroded steel), it is important to emphasize the chemical reaction(s) with the resultant free energy reduction, as well as the functional requirements (appearance, prevention of thickness loss) and the corrosion prevention treatments (barrier coatings like paint, galvanic coatings like zinc, etc.).
Regards,
Cory
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips Fora.
RE: Scientific name for rust?
You're not talking to a group of scientists or engineers. Keep it simple and if you can provide a demo for hands on it might make it interesting.
RE: Scientific name for rust?
What about the term "oxidised". The terms of corroded and rusted are just increasing more specific terms.
RE: Scientific name for rust?
RE: Scientific name for rust?
RE: Scientific name for rust?
Hg
Eng-Tips policies: FAQ731-376: Eng-Tips.com Forum Policies
RE: Scientific name for rust?