What is rust
metal corrosion manifests in the form of rust – damage to a surface that has a characteristic color. It is formed by oxidative processes when interacting with oxygen molecules found in water. Iron, breaking down, changes its chemical composition as well, decomposing into oxide and metahydroxide. Rust appearing on the iron does not stop the process of destruction, it provokes further destructive changes, which sooner or later cause deformation of metal and loss of it strength qualities. Therefore, in some cases, instead of iron alloys it is advisable to use non-ferrous metals alloys, although they are more expensive. In atmospheric conditions, for example, copper products and its alloys are covered with a thin layer consisting of corrosion products, but in this case the oxide film becomes a protection against the external environment.
Experienced and reliable owners, who had to face massive damage to the metal structures of a private house, fence gates or even window bars, say that corrosion of the metal is easier to prevent than then to get rid of it.
Prevention of rust
The easiest and affordable method to prevent corrosion of metal surfaces is their staining. Such a preventive measure will not require a great amount of money, but it is necessary to use special paints and ensure that good adhesion — coloring clutch layer with smooth metal surface.
To do this, all the old colorful layering must be removed with a hard metal brush or spatula, then pelt the surface with sandpaper or treat it with a grinder. The painted surface must be skimmed with white spirit or solvent and coated with anti-corosis priming composition suitable for this metal. Enamel or oil paint can then be applied to the treated surface.
Metal surfaces should be painted at temperatures ranging from +5 to +35°C and relative humidity not more than 80%.
When choosing a colorful coating, pay attention to its characteristics such as resistance to weather and temperature, as well as anti-corrosion properties. When painting, act gently and carefully paint all hard-to-reach places using special thin brushes. If you manage to completely cover the machined metal surface with a protective layer of paint, it will not form rust. But keep in mind that you should check the integrity of the coverage periodically and, if necessary, restore protection.
How to remove rust from a metal surface
Anti-corrosion formulations, which are used in both production and household, most often contain water, concentrated sulfur or Hydrochloric acid and inhibitors are special substances that prevent the metal from reacting with acids. That is why it is impossible to remove rusty plaque only with solutions of acids.
When working with acid-containing formulations, take precautions, protect your eyes and skin of your hands from cleaning agent.
At home, rust can be removed in several ways. Take a 0.5L 5% solution of hydrochloric or sulfuric acid, add 250ml of gurotropin to it and apply this mixture to a rusty metal surface, then wipe it until the rust disappears completely. In this solution it is also possible to hold small metal parts that have been subjected to corrosion.
A good result can be obtained by using a cleaning agent such as a mixture of Vaseline oil with lactic acid in a ratio of 2:1. Apply it to the surface, leave for half an hour, then remove the rust with a soft rag to which apply the Vaseline oil.
Rust can be removed with a 20% solution of orthophosphoric acid, it should be sprayed on the affected surface and let it dry completely, then rub the corrosive spots. Russian housewives for the same purpose use Coca-Cola, which contains phosphoric acid. The order of action with her is the same.
When acids are not available, as is often the case in household settings, try the following recipe. Mix half a cup of 20% vinegar, a teaspoon with a slide of coarse food salt and 2 tablespoons of flour. Remove the liquid dough that resembles sour cream in consistency and apply it to the damaged surface of the metal. After 30-40 minutes, remove the dough and repeat the procedure a few more times, until there is no trace left of the rust. The
easiest thing is to remove the rust with food soda and a hard metal brush. But this method can only be used when the surface of the metal is not afraid of scratches.