Oxidation is one type of corrosion that can occur on metals, and many alloys affect from oxidation. However, rust is specific to metals containing iron, which includes all types of iron (wrought iron, cast iron) and steel (carbon steel, stainless steel). Other non-ferrous metals like aluminium, copper or lead, can corrode, but they don’t actually rust.
Industrial rust removal for get rid of rust from pipes or machined parts includes all of the following methods:
- Strong acids and alkalis:Strong acids, like hydrochloric acid (AKA muriatic acid when diluted), as well as strong alkalis, react with rust and dissolve it. However, these caustic chemicals also eat away at most other substances too, and they are very dangerous to work with.
- Weak acids:Weak acids, like oxalic acid or EDTA react with rust less intensely than strong acids, with a slightly different reaction. These weak acids are less caustic and are safer to work with and they are easy to dispose of.
- Electrolysis:Electrolysis speeds up chemical reactions and destroys rust by applying electrical current to the reaction. This can also be dangerous and can produce toxic chemicals and fumes.
- Mechanical: Metal parts can be scrubbed and sand blasted to mechanically remove rust. This is hard work and can create noticeable unevenness that will affect the function or appearance of the part or equipment.
- Water-based solutions: Acid-free, water-based solutions use a different chemical process to react specifically with rust and remove it, leaving the underlying metal unaffected. They are the safest option to work with.