Formation Of Rust
Rust, which is technically known as oxidation, is the process that results when there is an interaction
n between oxygen and various metals for an extended time period. The oxygen and metal combine at an atomic level creating a new compound termed an oxide, and the metal bonds are weakened.
When iron or steel are the base metal, then the rust formed is called iron oxide (and similarly rusted aluminum is called aluminum oxide). Iron and steel are apparently hard in appearance, but the minute ruptures and pits in the exposed metal facilitate the penetration of water molecules, and rust is formed.
Rusting is an electrochemical process that is commenced with the move of electrons from iron to oxygen, and the process is expedited in salt water. With the passage of time, and availability of water and oxygen, an iron body will be converted into rust and be disintegrated.
Damage Due To Rust
Rust is a serious issue, and unless taken seriously in the initial stages,
may be uncontrollable and cause extensive damage by the deterioration, failure, or weakening of components or appliances. Rust is extremely harmful to cars. As the body is stained, the rust spreads to other parts of the car body if exposed to extreme moisture in the weather- and if appropriate rust prevention measures are not taken.
Electrical appliances and instruments may fail if the metallic parts are rusted since rust is a non-conductor of electricity. Similarly, the machines and equipment that use magnets may malfunction due to the inferior magnetic properties of rust.
Furthermore, since rust formation increases the volume of the initial iron mass, adjacent rusted parts may be forced apart, causing failure of the machines or assemblies. Rusting of iron in reinforced concrete bridges may be a source of serious structural problems that may be extremely dangerous, and also require huge expenditures for repairs.
Rust Prevention By Galvanization
Galvanization is an important metallurgical process for rust prevention that involves th
e application of a zinc layer, by electroplating or hot dip galvanizing, on the iron or steel object desired to be protected. In this process, iron or steel is dipped in melted zinc at a temperature at which there is a great similarity between these materials, and an alloy is formed, with a zinc coating at the exterior surface.
The coating of zinc protects the metal part object from oxidation and environmental effects like extreme temperatures, snow, wind, and rain. Zinc is used since its corrosion resistance characteristics are better than iron and steel, due to which it forms a physical obstruction against corrosion, and also shields the exposed steel if the zinc layer is damaged.
Galvanization is not successful at protecting joints and holes. However, it is widelye used for the protection of iron and steel because it is economical, simple in use, and long lasting.