Rust is a very common name and we hear it in our daily lives. It is the Iron Oxide which is formed due to Corrosion. Its chemical formula is Fe2O3. The process of rust formation is called rusting, which is an electrochemical process.

When iron comes in contact with the atmospheric moisture, water combines with the Carbon dioxide and forms carbonic acid. This acid dissolves the iron. Some water breaks down into hydrogen and oxygen. The free oxygen combines with the dissolved iron and iron oxide is formed. The chemical equation for the rusting process:

  • 2Fe(s) + 2H2O(l) + O2(g) 2Fe2+(aq) + 4OH(aq)
  • Fe2+(aq) + 2OH(aq) Fe(OH)2(s)
  • Fe(OH)2(s)  =O2=> Fe(OH)3(s)
  • Fe(OH)3(s) =dehydrates=>  Fe2O3.nH2O(s) {This is the rust.}


Now that we are aware of what rust is and how it is formed, it becomes an unwanted coating on the metal surfaces or machine tools. Rust formation of tools affects the tool, as it damages the surface and makes it rough.

Also Read: 18 Mechanical Properties Of Material Which Every Mechanical Engineer Should Know

Rust Removal Methods: