How to protect metals from corrosion? Types and methods + Video

As we know, any materials deteriorate under the influence of the environment and metal products and building materials are no exception, so consider the best methods of protecting metal from corrosion.

Corrosion cannot be completely removed, but it is quite possible to reduce its effect by increasing the service life of metal products.

A very important factor is the treatment of metal products and structures from corrosion, because this procedure will significantly increase their service life.

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Types of corrosion protection

Corrosion protection is conventionally divided into two types :

1. when it is used before the start of use of the structure or product and
2. when the product or structure is already in use.

The first type promotes high resistance to "chemical" attack.

Insulates direct contact with aggressive media (surface insulation).

The second type helps to reduce the aggressive environment (this will depend on the conditions of use).

Application of electromagnetic fields , for example, "overlay "external electric currents, density regulation and other techniques.

It also depends on the following factors :

1. Type of metal;
2. Operating conditions;
3. Difficulty of carrying out treatment with anti-corrosion compounds;
4. Economic feasibility;
5. Production capabilities.

Details of protection methods

All methods can be divided :

• active (which constantly affect the metal),
• passive (reusable),
• technological (used at the stage of sample production).

Active methods

Cathodic corrosion protection

This technique is used in cases where the medium in contact with the metal is electrically conductive. A large "minus" potential is applied to the material; this procedure prevents its oxidation.

Protective corrosion protection

Is cathodic polarization. The specimen is bound by contact with the material most susceptible to oxidation in this conductive environment (projector).

It is, as it were, a kind of lightning rod, that is, it takes all the negative of aggressive substances onto itself.

Anodic corrosion protection

This option is used very rarely, and it consists in maintaining the "inertness" of the material in relation to the environment.

Passive

Creating a protective film

Popular and low cost corrosion prevention technique.To create a surface layer, special substances are used.

These substances must be inactive with respect to aggressive chemical compounds, be non-conductive and have good adhesion.

Before use, all substances for metal processing are in a liquid or aerosol state, the method of application will depend on this.

To process metal, paints and varnishes, various polymers or mastics are used.

Metal structure in "gutters" for protection

Used for pipelines and engineering systems. In this case, an air gap acts as an insulator, which is located between the inner walls of the channel and the metal.

Phosphating

Metals are also treated with special oxidants. Such oxidants enter into a reaction with the base and, as a result, deposits of poorly soluble chemical compounds are formed on its surface.

Metal coating with resistant materials

In this case, metal products are "chrome plated", "galvanized", silver and the like. Concrete, glass, ceramics, cement mortars and so on also act as metal protection.

Passivation

This manipulation consists of in order to sharply reduce the chemical activity of the metal. In this case, the metal surface is treated with special reagents.

Reducing the aggressiveness of the environment - the use of substances that reduce corrosive processes (inhibitors).

Air dehumidification is a chemical purification of air from various harmful impurities and the use of other techniques that are applicable in everyday life.

Soil hydrophobization is filling it with special substances to reduce soil aggressiveness.

Treatment with pesticides - used in cases where there is a possibility of biocorrosion.

Technological method of protection

Alloying - an alloy resistant to aggressive influences is made on the basis of the metal.

And since you understood from the above information, not every method of anti-corrosion treatment can be used in a domestic environment.

That is, it turns out the possibilities of a "private trader" are very limited.

In this article, we have described several methods of anti-corrosion treatment of metals and we hope that this information was useful to you. We wish you good luck and patience!