What Makes Cars Rust?

Rust is the bane of all cars. From the decades-old classic to the newest hybrid, all cars have parts that are made of metal and are, therefore, susceptible to rust. Rust is so insidious that the smallest paint scratch can encourage it and strong enough to eat through the bodywork and chassis if not stopped. What is rust really, though?

Rust is iron oxide. The oxidation of iron is a chemical reaction requiring moisture and oxygen. The three types of iron oxide are black powder, expressed as FeO, reddish-brown powder, expressed as Fe2O3 and a hybrid of the first two, expressed as Fe3O4. Without moisture, rust is impossible. If you could seal an iron nail in a jar of pure oxygen, with no water present, the nail would not rust. If you put water in the jar, the nail would rust quite soon. Throw salt into the experiment and the "rust monsters" will soon eat up your nail.

When iron comes into contact with H2O, it creates a solution tension. The results will vary depending on the surface and its electron concentrations. On parts of the surface with a fairly positive electron charge, the iron dissolves and forms positive iron II ions. Electronegative portions of the surface form OH-, (negative hydroxyl) ions instead. The OH- ions then bond with the iron to create hydroxides. These bonds cannot be dissolved. When combined with hydrogen (an important component of water) iron II ions become iron III ions. The hydroxide ions and iron II ions react and create hydrated iron oxides. Let them dry and you've got rust.

Higher levels of hydrogen accelerate the rusting process, as does the presence of salt because it increases the water's electrical conductivity. This is one reason winter is so hard on cars, because the road salt increases the chance of rust. While rust can usually be prevented with proper maintenance, it sometimes gets the better of even very careful automobile owners.

If your car's body, wheels or chassis do suffer rust, you can sometimes grind it out and use a sealer to prevent the rust from spreading. If the rusting is sufficiently advanced to require replacement of the part, there are affordable options. Instead of paying an auto body shop an arm and a leg to fix the rust damage, you can often obtain affordable car parts from car breakers or a car salvage shop.

Searching online for car breakers. can save you a lot of time and money over going to an auto body shop or hunting through junk yards for the car part you need. By shopping online car salvage sales you have the advantage of looking through a wide selection of components without even leaving the house. Have your parts shipped to you and start restoring your car right away.