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How to "defeat" rust on the car

How to get rid of rust

It happens, when on the roof of the car a dotted, but deep enough dent is formed. It does not look like a big branch with a sharp bough or a small stone from the balcony above the parking lot ... And what I saw in a few weeks on the spot of this dent is not exactly nice - rust :( Edition shram.kiev.ua tells how to deal with rust on the car and picked up advice from personal practice to remove rust.

Rust is a common term for the determination of iron oxides. In colloquial speech, this word is applied to red oxides formed during the reaction of iron with oxygen in the presence of water or moist air.

There are other forms of rust, for example, the product formed during the reaction of iron with chlorine in the absence of oxygen. This substance is formed, in particular, in the reinforcement used in underwater concrete poles, and call it green rust. Several types of corrosion can be seen visually or with the help of spectroscopy, they are formed under different external conditions. Rust consists of hydrated iron (III) oxide Fe2O3 · nH2O and iron metahydroxide (FeO (OH), Fe (OH) 3) . In the presence of oxygen and water and sufficient time, any mass of iron eventually becomes completely rusted and destroyed. The rust surface does not create protection for the underlying iron, in contrast to the formation of patina on a copper surface.

Rust, as a rule, is called the product of corrosion of only iron and its alloys, such as steel. Many other metals are also corroded, but iron oxides are usually called rust.

So, what is it - all the familiar rust, or speaking more scientifically - iron oxide Fe2O3. Rust is only capable of iron or its alloys, which are oxidized after the metal is combined with water. Corrosion of metal is an electrochemical process in which electrons are emitted from the anode (its role is played by the metal body of the car), which through the electrolyte (water even with a small admixture of salts) enter the cathode (metal parts that can receive electrons). As a result of this process, the car body iron is converted to iron oxide - that is, rusts.

Understanding the corrosion process and gives us the tools to deal with it. Since the car body is made of iron, the anode and cathode will always be found, but with electrolyte we must do something. By the way, it is because of the greater saturation of the various salts of chemical reagents that use public services in the fight against ice, the machine starts to rust violently during this period (electrolyte is very saturated and qualitative).

The process of corrosion control is multistage and is divided into three fundamentally different directions.

The first way is passive. Since we can not replace the car body iron with, for example, plastic (brittle enough) or for metals without iron (expensive), we need to cover the metal of the body with an insulating coating - i.e. primed and dyed. This process is the most effective way to prevent corrosion - but it is necessary to constantly monitor the integrity of the protective coating, to check it for minor damage - cracks, shocks, chips. If detected, immediate measures should be taken to restore the coating.

Also, this includes measures related to the cleanliness of the car - washing (every two weeks) and periodic (after every second washing) treatment with wax coating the machine - wax flows faster from the coating on the wax.

Waxing is the second way to combat corrosion, called active, that is, the use of various physical and chemical coatings on the metal. For this, various mastics, sealants, protective lubricants and anticorrosion sprays are used. There are a lot of them, but the essence is one - the creation of an additional protective layer in addition to the main paintwork. Basically, these drugs are used on the most prone to corrosion areas of the machine - the bottom, thresholds, arches. Additional protection is effective only when applied to absolutely clean and dry surfaces, otherwise under the protection film there may be water, which will continue the corrosion process.

The third way - electrochemical - is used less often, primarily because of the high cost and the need for constant power supply of an additional electronic device (cathodic protection station). We can roughly say that due to a change in the electrode potential, corrosion processes in the car begin to pass only in a certain place, and the cathode is now not the body of the machine, but a special electrode that rusts instead of it. There was also a newer, purely electronic system, the "Finale-Coat", which forms a uniform flow of free electrons on the body of the machine, which do not interact with the atoms of the metal.

All three ways of protecting the body perfectly complement each other, but still sometimes there is a blunder and the process of appearance of rust shows itself in all its brownish-red beauty. There is already need to act quickly, since it is very easy to start the corrosion process throughout the body, but getting rid of it is much more difficult.

First of all, you need to carefully remove the rust . To do this, use a weak solution of alkali acid, which is treated with rust, and then it is removed mechanically (nazhdachkoy or metal brushes). Carefully observe the requirement of the instruction, since the acid is aggressive enough and simply corrodes the rust from the inside, and this process needs to be stopped in time.

Also effective are the so-called rust converters or modifiers, which, as a result of the chemical reaction, convert iron oxide to iron tannate, which is a more stable substance. Qualitative modifiers contain polymers and act as primers. The disadvantage is that if the metal oxide is not processed in the entire volume and remains, the corrosion process will continue.

Now in specialized stores it is easy to find the very same rust converters of various kinds. Their cost is not very high. The processing process is very simple, first we sand the damaged area to a clean metal, then we apply the rust converter composition and leave it for several hours depending on the instruction. Do not be alarmed when the cleaned area is green, - it works a rust modifier.

Then everything is standard - the place from which the rust was removed (or transformed) is shpaklyuetsya, primed and painted. Actions are repeated if necessary. In my case, I decided to use the modern and most reliable and persistent, in my humble opinion, method - galvanizing. The process is also an electrochemical process, and as a result of the electrolysis of a solution containing zinc, a zinc protective layer that is not prone to rust appears on the surface of the iron.

Theoretically, it was possible to prepare for this process independently, but I preferred to buy a ready-made set consisting of two bubbles with liquids (plus auxiliary things). The first is designed to remove rust and degrease the surface (I rusted the rust mechanically - it was not good - but still ...). Then I moistened a special swab in the contents of the second vial - a solution of zinc salts - and with the help of the attached wiring connected to the battery, I started the electrolysis process.

As a result, I was: a) terribly pleased with my technical and chemical advancement; b) made up for the psychological loss from a set of a young chemist, not yet bought in my childhood; and c) received on the body of a thin layer of protective zinc coating of gray color (and a blister with my paint I have so I have).

So you can and should fight rust on the car, and now you also know how.

Via autokolonka.ru & wiki