How to protect against corrosion

Description and types of body corrosion protection

It is known that metal surfaces of vehicles must be coated with anti-corrosion agents. The fact is that even with careful care, the body is constantly influenced by external physical and chemical factors, as a result of which rust forms. Anti-corrosion coating greatly helps to extend the life of the body and the car as a whole.

What is corrosion, why does it form and why is it dangerous?

Corrosion is the destruction of metal due to its chemical reaction with water and oxygen. During movement, the unprotected surface of the body and other parts is constantly exposed to mechanical stress and comes into contact with air, which contains oxygen.

Car body corrosion

Atmospheric precipitation, in turn, contributes to the ingress of moisture onto the metal, and in hard-to-reach places of the car, moisture evaporates for quite a long time. The reaction of iron with water and oxygen leads to the formation of destructive rust.

Rust is one of the most serious “diseases” of the body. Its spread leads to a weakening of the vehicle's power structure and reduces the level of passive safety in a collision.

The most vulnerable places

Due to its complex design, the body rusts unevenly. The most vulnerable places include:

1. Welds. Welding cannot ensure complete sealing of parts, so there are always microcracks in the seams. With constant humidity, it is in the welding areas that primary foci of corrosion form.
2. Bottom, wheel arches, niches and sills. These places are constantly faced with mud, sand and rocks. When driving a car at speed, the physical impact becomes very noticeable, so corrosion forms quite quickly.
3. Engine and exhaust system. A running engine has a high temperature, which is very different from the ambient temperature. Constant temperature changes also cause corrosion.
4. Interior of the body. The interior gets dirty and wet easily even after short trips.

All these places require different protection, since the causes of corrosion are not the same.

Why additionally process the body if it is done at the factory?

Many motorists believe that only old cars with impressive mileage are susceptible to corrosion, and new cars do not need additional anti-corrosion treatment. In reality, this is far from the case, since the manufacturer's treatment is rather designed to protect the car from manufacturing defects.

In real conditions, the car is constantly exposed to aggressive factors: high humidity, chemicals on the roads, and even acid rain.

The manufacturer rarely takes into account the influence of such conditions, and the quality of factory processing is not always at an acceptable level.

Anti-corrosion treated bottom

Many cars are galvanized during production, however, this measure is also not a panacea for corrosion. The thickness of the zinc layer is very small, so various mechanical damage and vibration loads easily destroy it.

Types of protection

Many types of anti-corrosion treatment have been developed to protect the car:

1. Active. It is carried out using products that interact with metal and repel moisture.
2. Passive. This includes barrier protection, for which various types of coatings or linings are used.
3. Transformative. Includes products that help get rid of rust that has already appeared on the body.
4. Complex. It involves the use of several methods at once.

Electrochemical protection is sometimes included in a separate category.

Electrochemical method

A very effective method with which you can achieve the same high result as with galvanizing. The essence of this method lies in the peculiarities of chemical reactions between metal, oxygen and water.

According to the laws of physics and chemistry, it is necessary to create a difference in electrical potentials. An element with a high potential is oxidized, and an element with a low potential is reduced.

Thus, to protect the metal from oxidation, it is given a negative potential. The advantage of this method is the anti-corrosion effect even in hard-to-reach parts of the body.

Cathodic protection

Most often, electrochemical protection is carried out using the cathodic method. In this case, the metal of the body acquires a negative potential and is restored. To shift the potential, it is necessary to ensure the passage of current, which is performed using a special device.

The corresponding electronic module can be purchased or manufactured manually, then installed in the cabin and connected to the on-board network.

Example of cathodic protection connection diagram

The device must be turned off periodically, since a negative effect is observed with a strong potential shift.

As an anode - an element that will have a positive potential and experience oxidation - you can use a metal garage or grounding in an open parking lot. When the car moves, the anode is grounded to the road: to do this, just attach a rubber strip with metal elements to the bumper. When driving, a potential difference is formed between the body and the road.

Anodic protection

When using anodic protection, it is necessary to install copper, aluminum or zinc plates on the body, which will oxidize and “pull” the destruction process onto themselves. As a rule, they are placed on the mounts of headlights, mudguards, and the inner surfaces of thresholds or doors. The disadvantage of this method is the installation of plates, which still cannot cover the entire body.

Anodic protection element

Barrier methods

Often, corrosion forms in specific areas that frequently come into contact with water or experience physical damage. Such places can simply be covered with mechanical barriers, which will significantly slow down the rate of its occurrence.

As a rule, the barriers are:

1. Special primers and mastics that carefully cover the surface of the body.
2. Plastic linings. Typically, special fender liners are installed on the wheel arches, the sills and the bottom of the doors are covered with body kits, and there are also plastic elements or leatherette linings on the front and rear edges of the hood.
3. Lamination. The use of film made from vinyl or polyurethane. The body, covered with film, is reliably protected from stones, various minor damage, exposure to the sun and moisture.

Typically, motorists combine several methods of barrier protection.

Application of anti-corrosion coating

Combined corrosion protection

The combined method involves the use of several methods to combat corrosion. For example, you can use plastic linings and apply moisture-repellent compounds. Other car owners prefer to use cathodic protection and special primers.

Any car is inevitably susceptible to corrosion, and the factory coating is not always a reliable anti-corrosion agent. To extend the service life of the body, it must be comprehensively protected from destruction almost from the very beginning of the vehicle’s operation.

Source: https://TechAutoPort.ru/nesuschaya-sistema/pokrytie-kuzova/zaschita-ot-korrozii.html

How to protect metal products from corrosion?

Corrosion has a destructive effect on metal products and alloys. When interacting with the environment, metal products become stained with rust. The more active the metal, the more susceptible it is to corrosion.

Corrosion has a destructive effect on cars, ships, communications and other metal products, which can lead to leakage of oil, gas and other negative consequences. It negatively affects human health, and oxidation products pollute the environment.

Corrosion is unacceptable in the aviation, chemical and nuclear industries. Sometimes the cost of repairing metal products exceeds the cost of the material that was used to manufacture them.

Main types of corrosion processes

Types of metal corrosion can be divided according to the following characteristics: nature of destruction, corrosive environment and mechanism of action.

Based on the nature of the damage, corrosion can be:

• solid. At the same time, it can be uniform and uneven. When uniform, the entire surface of the product is destroyed. When uneven, spots and pinpoint depressions appear;
• intercrystalline. In this case, it penetrates deep into the product along the grain boundaries of the metal;
• transgranular, in which the metal is cut through a grain by a crack;
• selective. One of the components of the alloy is destroyed. For example, zinc in brass can deteriorate.
• subsurface. It starts on the surface and gradually penetrates into the upper layers of the metal.

The following types of corrosive environments exist:

• atmosphere;
• gas;
• the soil;
• liquid (alkali, acid or saline solutions).

The mechanism of action divides corrosion into chemical and electrochemical.

Chemical corrosion is a process in which spontaneous destruction of metals occurs. It occurs when metal products interact with an actively corrosive environment, most often gas. These processes are accompanied by high temperatures.

As a result, simultaneous oxidation of the metal and restoration of the corrosive environment occurs. Chemical corrosion also occurs when interacting with organic liquids, for example, petroleum products, alcohol, etc.

Electrochemical corrosion occurs in electrolytes, for example, in aqueous solutions. The electrochemical reaction produces an electric current that causes the metal to break down. In this case, both chemical processes occur, in which electrons are released, and electrical processes, in which electrons move.

Fracture occurs when dissimilar metals come into contact. Therefore, metals containing many impurities are more susceptible to destruction.

The heterogeneity of the metal structure leads to the fact that during electrochemical corrosion, cathode-anode pairs are formed according to the laws of galvanics. If metal products differ from each other in chemical composition, then a layer of rust forms on the surface of the metal products.

This corrosion is most often the reason for the destruction of metals. Below are pictures showing the mechanism of action of electrochemical corrosion.

In the external environment, metal products are most actively affected by oxygen, high humidity, oxides of sulfur, nitrogen, carbon dioxide, and groundwater. Salt water accelerates the oxidation process, which is why sea vessels rust faster than river vessels.

It is impossible to stop this natural process; all that remains is to find ways to protect against corrosion. True, it is impossible to completely get rid of the corrosion process, but these methods help slow down the process itself.

The following methods exist to protect metals from corrosion:

• increasing the resistance of metals by increasing the chemical composition;
• insulation of metal coatings from aggressive environmental influences;
• reducing the aggressiveness of the environment in which metal products are used;
• electrochemical, which, thanks to the laws of galvanics, reduce corrosion processes.

These methods can be divided into two large groups. The first two methods are applied before metal products are used, that is, at the stage of their production. In this case, certain construction materials are selected for the production of the product, and various galvanic and protective coatings are applied.

The last two methods are used when operating metal products. In this case, for protection, current is passed through the product, the aggressiveness of the environment is reduced by adding various inhibitors, thus, the product itself is not pre-treated in any way before use.

Methods for increasing resistance

These protection methods are based on the creation of alloys that have anti-corrosion properties. Components are added to the metal to increase its corrosion resistance. An example is alloying steel with chromium.

The method is used in the production of steel. The result is chromium stainless steels that are resistant to corrosion. They increase the anti-corrosion characteristics of steels by adding nickel, copper and cobalt.

Rust does not appear on these surfaces, but corrosion is present. Corrosion is slowed down due to the fact that one atom of an alloying additive is added to eight iron atoms, and this streamlines the arrangement of atoms in the crystal lattice of the solid solution, which prevents corrosion.

Corrosion resistance can be improved by removing impurities from metals or alloys that accelerate corrosion. For example, iron is removed from magnesium or aluminum alloys, sulfur from iron alloys, etc.

Reduction of environmental aggressiveness and electrochemical protection

Reducing the aggressiveness of the external environment is achieved by removing substances from it that are depolarizers, or by isolating metals from the depolarizer. Removing oxygen from a medium is called deoxidation.

To slow down the corrosion process, special substances - inhibitors - are introduced into the environment. They can be either organic or inorganic. Inhibitor molecules are absorbed by the metal surface and, thereby, contribute to a sharp decrease in the rate of metal dissolution and prevent the occurrence of electrode processes.

With electrochemical protection using an external electric current that passes through the metal, the potential of the metal shifts and, thereby, the rate of its corrosion changes.

Depending on the potential shift, electrochemical protection can be cathodic and anodic. These methods are used to protect drilling platforms, welded metal foundations, underground pipelines, and also protect the underwater parts of sea vessels.

Film protection

In order to protect metal products from corrosion, a protective coating can be applied. Varnishes, paints, enamels, plastics, etc. can be used as coatings.

Paint and varnish coatings are easy to apply, inexpensive, have water-repellent properties, do not react chemically with metal, and fill pores and cracks well. They serve to protect metals from environmental components that cause corrosive processes.

If you choose the right paint materials and follow the technology for their application, they can serve as a coating for up to 5 years.

Often a primer is applied under the paintwork, passing through which water dissolves some pigments and becomes less corrosive. Instead of a primer, the surface can be phosphated. They are applied with a brush or spray. For steel products, most of these preparations consist of mixtures of manganese and iron phosphates.

You can protect a metal product by applying a layer of metal that is more corrosion-resistant. In this case, corrosion destroys the coating itself. Such metals are chromium, nickel, zinc. For example, iron is coated with chromium.

Products made of copper, brass, as well as sheet steel are coated with zinc. Such coatings are called anodic; they provide electrochemical protection. Their service life depends on the thickness of the applied coating. There are also cathodic coatings.

They serve for mechanical protection of the base metal. If this coating is damaged, the anti-corrosion protection ceases to be effective. In addition, this accelerates the corrosion process.

An example of such a coating is the coating of iron with tin. When comparing the effectiveness of anodic and cathodic coatings, it is better to use the anodic one, since it works even if the integrity of the coating is damaged.

There are various methods for producing metal coatings. With the hot method, the coating is obtained by lowering the product into hot metal.

If the product is coated with tin, this process is called tinning, if with zinc - galvanizing. The coating can be applied using the galvanic method by depositing salts from the electrolyte on the product.

When using the spraying method, a plasma jet of molten metal is sprayed and applied to the surface to be protected. Metallizers are used for spraying.

When cladding, joint hot rolling of the base and protective metal is carried out. Metals adhere to each other due to diffusion.

Source: http://StrojKarkas.com/materialy/sposoby-zashhity-metallov-ot-korrozii.html

How to properly protect your car from corrosion

From the moment people began to use iron in the production of vehicles and all kinds of metal structures, corrosion, the impact of which leads to serious damage, began to attract the attention of researchers. This happened in the 30s of the 20th century, when the automotive industry was developing very actively.

It was then that the Swedish company AB Tikamin was created, later renamed the Dinol AB concern.

To date, its specialists have developed a wide range of anti-corrosion materials, which are sold under the Dinitrol brand, known throughout the world.

Let us note the important fact that the Tikamin company became one of the founders of the anti-corrosion materials market. Therefore, now the Dinol AB concern has very extensive experience in the development and production of compositions for various applications.

What is corrosion?

Corrosion is a rather complex process. But even without delving into the basics of chemistry, you can understand its reasons. From the point of view of the average person, corrosion turns iron into rust. This process occurs in the obligatory presence of two components - water and oxygen. Obviously, both of these substances are found in excess in the atmosphere and it is almost impossible to completely isolate the metal from their effects. Water (together with various elements dissolved in it) is often called an electrolyte.

Other circumstances may also affect the rate of corrosion. For example, salt, or rather, chlorine ions, as well as impurities in industrial emissions, is a powerful corrosion accelerator. And if you consider that in winter the roads of large cities in our country are regularly treated with one or another reagent based on various salts, then you can understand why the problem of anti-corrosion protection of cars is so pressing in Russia.

But not only the presence of certain chemical elements affects the rate of corrosion. For example, it increases with increasing humidity or temperature, which imposes restrictions on the functioning of the exhaust system, engine compartment and poorly ventilated hidden cavities.

Corrosion problems are also of particular concern to motorists in Scandinavian countries - there, as in Russia, winter lasts longer than all other seasons. Therefore, it is no coincidence that Sweden is a trendsetter in the market of anti-corrosion compounds, and Dinol AB is one of its main leaders.

Automotive specifics

Corrosion of a car body has many specific features. It is known that its different sections corrode at different rates, because... during operation they are in different conditions. One of the main weak points is the welds, with the help of which the structure retains its shape. This is where rust spots most often occur.

The fact is that in welding areas there are always microcracks that can easily be filled with moisture. In the mechanism of crevice corrosion, vehicle vibrations during driving, as well as temperature changes in winter, play an important role. In the latter case, moisture, turning into ice, widens the gap, because in the solid state it occupies a larger volume.

Therefore, the next time the resulting gap will be filled with a large amount of water, which, when frozen, will increase it again. This seemingly simple cyclical process ultimately leads to serious consequences.

It should also be noted that the corrosion resistance of steel at seams is significantly lower due to the effect of high temperature at the time of welding on both the steel itself and the galvanic coating, if present.

Due to its design features, a car body has a large number of internal cavities. Not only are they hidden from the motorist’s eyes (this often leads to late detection of rust), but they are also poorly ventilated. As a result, water and other substances harmful to the metal accumulate there and a zone of high humidity is formed. So corrosion in hidden cavities occurs especially quickly and, most dangerously, unnoticed.

Another vulnerable area of ​​a car body to corrosion is the underbody surface. And this is quite obvious, because... the constant mechanical impact of crushed stone and sand, along with water and salt, flying in excess from under the wheels, is able to “break through” even reliable protective coatings.

The operation of the car's engine and exhaust system can also cause rust, because... the functioning of these nodes is associated with a significant increase in temperature.

Thus, a modern car, having a complex body structure, is very susceptible to corrosion. Moreover, from the point of view of protection, its different components require an individual approach, which significantly complicates the anti-corrosion treatment procedure.

About the reliability of factory protection

Owners of many foreign cars have the opinion that their cars do not need additional anti-corrosion treatment, because... The manufacturer has already taken care of everything on the assembly line. And if this car is equipped with a galvanized body, then this opinion turns into real conviction. But, as it turns out, reality is somewhat different from expectations. But first things first.

In addition to galvanizing, which is gaining popularity in developed countries, various priming methods are used to protect against corrosion. In the production of domestic cars, the so-called anaphoresis method is more often used. In the developed world, it has long been morally obsolete, because... demonstrated low levels of anti-corrosion resistance. Nevertheless, in our country it is used very actively.

The cataphoretic priming method is more effective. But as actual operation has shown, without additional anti-corrosion treatment, such bodies also succumb to rust quite quickly. This method is being used more and more actively in Russia. For example, new VAZ models, as well as many foreign cars, are processed in this way.

Finally, the most effective way to combat corrosion at a factory is galvanizing. In the automotive industry, the accepted thickness of zinc coating is 6-9 microns. On a test plate with such a thickness of galvanic zinc, when placed in a full-scale test station (for example, an industrial zone of a large city), the first signs of corrosion appear on average after 9-12 months.

This is explained by the presence of micropores in the zinc coating, through which air moisture, along with all impurities, penetrates to the metal, and the process is completed. The thicker the zinc coating, the less likely it is that the micropores “coincide”, and the more reliable the protection. Each additional micron of zinc coating increases the weight of the vehicle and thus fuel consumption.

Therefore, a compromise was found - 6-9 microns of zinc coating, which significantly reduces the corrosion resistance of the car and does not increase fuel consumption so much. Indeed, galvanized bodies “live” much longer. But not as long as is commonly thought.

Their lifespan, firstly, depends on the thickness of the galvanic coating, the type (double-sided or one-sided), and most importantly, on the presence of damage during operation. The latter are almost impossible to avoid, because...

they appear during spot welding, when not only does a thin layer of zinc “burn out”, but also the exposed steel forms a galvanic element with zinc at the welding site, thereby accelerating the onset of corrosion. Therefore, even galvanized bodies, after several years of operation, suffer from corrosion in the absence of additional support from anti-corrosion materials.

https://www.youtube.com/watch?v=cDrUiUXBZ2U

This fact is confirmed by the results of independent studies of more than 100 cars of different brands and models produced no earlier than 1998, conducted by the authoritative Swedish magazine “Vi Bilagare”. As can be seen from the results table, only a few manufacturing companies provide high-quality factory corrosion protection, while the majority of models received an “unsatisfactory” rating.

So it makes sense for owners of even prestigious foreign cars to pay attention to the issue of anti-corrosion protection of their iron horses, not to mention the owners of ordinary models. Those who underestimate the harm of corrosion to a modern car and blindly believe in the manufacturer’s long-term advertising guarantees should carefully read the written warranties and the conditions for their preservation.

Practice shows that 99% of attempts to make claims to the manufacturer for corrosion resistance end unsuccessfully. Referring to non-compliance with operating conditions, the manufacturer, or rather, the seller-dealer representing him, refuses compensation for damage. Insurance companies describe compensation for damage from corrosion even more harshly - damage caused by corrosion is not compensated at all.

Considering that car corrosion experts from the Corrosion Institute (Sweden) insist that after 3 years of operation traces of corrosion can be found on all cars without exception, there should be much less optimism about “stainless” modern cars.

RATING "VERY GOOD"	RATING "UNSATISFACTORY"
Audi A2	2000	12	Alfa 156	1998	8
Audi A4	1998	12	Alfa 166	1998	8
Audi A6	1998	12	Cadillac Seville	2000	6
Saab 9-5	1998	6	Chevrolet Alero	2000	6
Seat Leon	2000	12	Chrysler Voyager	1998	7
Seat Toledo	1999	12	Chrysler PT Cruiser	2000	7
VW Lupo	2000	12	Citroen Xantia	1999	6
VW Polo	2000	12	Fiat Punto	2000	8
VW Beetle	1999	12	Fiat Multipla	2000	8
VW Bora	1999	12	Ford Fiesta	2000	6
VW Golf	2000	12	Ford Escort	1998	6
Volvo S60	2000	8	Ford Mondeo	2000	6
Volvo S70	1999	8	Ford Scorpio	1998	6
Volvo S80	1999	8	Honda Civic	1998	6
RATING "GOOD"	Hyundai Atos	1999	6
BMW 318	1998	6	Hyundai Accent	2000	6
BMW 528	1998	6	Hyundai Sonata	1999	6
Lexus IS 200	1999	12	Kia Sephia	1999	5
Mercedes C-class	1999	30	Lada 110	2000	6
Mercedes E-class	1998	—	Mazda Demio	1999	6
Mitsubishi Carisma	2000	10	Mazda 323	1999	6
Opel Astra	1999	12	Mazda 626	1999	6
Peugeot 206	1999	6	Mazda Premacy	2000	6
Saab 9000	1998	6	Mitsubishi Lancer	1999	6
Skoda Felicia	1997	6	Mitsubishi Galant	1998	6
Skoda Fabia	2000	10	Mitsubishi Space Star	1999	6
Skoda Octavia	1998	10	Mitsubishi Carisma	1997	6
Toyota Prius	2000	12	Nissan Micra	1997	6

Source: http://dinitrol.ru/kak-pravil-no-zashhitit-avtomobil-ot-korrozii/

Protecting your car from corrosion

Car anti-corrosion treatment

:

Body corrosion is the appearance of rust and the destruction of the metal body of a car under its influence. For the manufacture of automobile bodies, steel is often used, which, under the influence of the environment, begins to oxidize, thereby disrupting the structure of the metal and beginning to collapse. Restoring a rusty body is a very complex and expensive process, so the destructive effects of corrosion should be prevented in advance.

Nowadays, corrosion, although not a pleasant problem, is solvable. To combat it, you need to know which parts of the body are most susceptible to it, and what the mechanism of corrosion occurs, as well as what means should be used to eliminate it.

Average imported cars are designed for 10 years of operation when stored in a garage, and with good quality road surfaces. In the CIS countries, these two points cannot always be observed.

To prevent body rusting, you should know the factors that contribute to it:

• Condition of the roads. When driving on a bad road, the body is damaged by small stones, forming microscopic chips, and when driving through potholes, the body begins to vibrate and cracks grow;
• Winter period. In winter, roads are treated with salt; upon contact with the body of salt, the aggressive environment begins to destroy any protection of the body coating;
• Body quality. The rate of corrosion depends on the presence of special additives in the metal. So, for example, if you take budget cars from twenty years ago, then at present there is not a single one whose body has been preserved today without traces of corrosion, unlike expensive brands of that time, in the production of which the body was made of metal alloyed with special additives ;
• Humid climate. In regions where there is high humidity, especially on the coasts near the seas, corrosion occurs much faster, since water particles in contact with metal oxidize it more than air.
• Sudden changes in temperature. In winter, when a car is driven from the cold into a warm garage, condensation begins to form on the body, thereby creating conditions for the metal to rust.

The process of treating a car against corrosion

Immediately before treating the car body against corrosion, the rust should first be removed. Rust is removed mechanically, using special devices, such as sandpaper, an angle grinder with an emery wheel, or sandblasting, the latter method is the most effective.

To speed up the rust removal process, you can use special solutions such as hydrochloric acid. The most effective way to combat corrosion is the use of converters or modifiers. When applied to rust, a chemical reaction occurs in which iron oxide (rust) is converted to iron tannate.

To process the body, you do not need to have special skills, just follow the following sequence:

• The very first thing you should do is degrease the surface, since if you treat a dirty surface with anti-corrosion substances, then there is simply no point in applying them; alcohol or paint thinner - white spirit - can be excellent for degreasing.
• The method in which you treat the body against corrosion depends on the size of the rust. If the rust is not significant, then it is enough to use sandpaper to remove it. If the corrosion has grown deep into the metal and on the sides, then removal will require using a brush with metal teeth or a grinder with an abrasive wheel. For a better effect during removal, it is recommended to use special solutions of orthophosphoric or hydrochloric acid, which, with their aggressive environment, soften the rust, making it easier to remove.

IMPORTANT! After removing rust using solutions, it is imperative to treat the places where the chemicals come into contact with the metal, since the remnants of one or another substance provoke the development of new rust.

• In the final process of getting rid of corrosion, the cleaned parts of the body must be primed. The order should be followed: epoxy primer is applied first, and acrylic primer is applied on top of it.

Anti-corrosion agents

Currently, there is a large selection of anti-corrosion agents that can be used to protect the body from rust, each of which has its own advantages and disadvantages. Automotive stores can provide you with the following products:

• Paraffin compounds. They have the advantage that they dry immediately after application, forming an elastic protective layer that can retain its properties during temperature changes;
• Bitumen mastic. Includes synthetic and bitumen resins that protect the body by preserving the metal;
• Oil-based anti-corrosion agents. They are used in a liquid state, due to which they completely fill various cracks with their composition;
• Polyvinyl chloride rubber materials. They are mainly used by the manufacturers themselves, as they are reliable and durable;
• Liquid plastic. It is used mainly as additional protection, due to its low mechanical stability.

This method is a purely mechanical way to protect the body from rust; there is another method, the so-called passive method of protecting the metal body thanks to its galvanization, which can also be done at home using special tools and equipment. The processing sequence is as follows:

• Remove rust with sanding materials as much as possible;
• The car is put on the handbrake and the engine is started. The drive included in the special device is connected to the positive terminal of the battery. It is possible to carry out the procedure with the engine turned off, but this is not as effective;
• the second end of the wire is connected to the red electrode. To create a galvanic effect, the machine body must be grounded;
• at the end of the electrode there is a sponge designed to absorb moisture; it must be dipped in a solution to remove rust, and then thoroughly rub the composition over the affected area;
• after removing traces of corrosion, it is necessary to wash off the remaining solution with water;
• the next step is to disconnect the red electrode and connect the gray one;
• dip the gray electrode sponge into the zinc solution and treat the surface again until there is a sufficient layer of zinc on it.

Practice shows that galvanizing an engine is the most effective method for combating and preventing corrosion.

Engine and exhaust system corrosion protection

Parts inside the car are also vulnerable to corrosion. The fuel combustion and gas exhaust system operates in aggressive conditions. On the one hand, they are exposed to high temperatures, acid vapors and moisture condensation, and on the other, to water, stones, salt and dirt.

Corrosion in places hidden from view occurs due to the formation during combustion of a fuel mixture - water, carbon oxides, nitrogen and sulfur. According to their chemical characteristics, these substances are strong metal oxidizers.

In the muffler itself, with the constant formation of carbon deposits and temperature changes, the metal is especially susceptible to stress and easily corrodes.

To protect the internal parts of the car from rust, the means that are used to protect the body are not suitable, since the temperature of the exhaust gases is usually within 400 degrees, and the temperature of the metal of the exhaust pipe during operation can heat up to 300 degrees. Therefore, to protect against corrosion, you need to use only heat-resistant enamels and varnishes.

REFERENCE! To increase the heat resistance of enamels and varnishes, aluminum powder is added to them.

In addition to withstanding temperature, special substances must also have good adhesion, salt and moisture resistance. Structural elements are painted with protective substances using pneumatic spraying. The surface of the engine during operation can heat up to high temperatures.

The main causes of engine corrosion are: oils, dust and soot, which accumulate on various parts assemblies, creating a durable film. Before anti-corrosion treatment, the engine should be cleaned of dirt and traces of oil. Materials for engine corrosion treatment are based on petroleum products.

They also contain corrosion inhibitors, surfactants, binders and fillers. Part treatment agents have good wetting properties and easily penetrate into tight spaces, saturating them and slowing down the rusting process.

When it comes to treating the underbody of a car, anti-rust substances must primarily be resistant to moisture and high vibration.

Every car owner should know that the risk of corrosion always exists; it is worth saying that when assembling cars on an assembly line, their body already at that stage begins to undergo metal oxidation processes. Therefore, you should always pay due attention to the condition of the body and, if the slightest defects related to corrosion occur, take appropriate measures.

Source: https://rulikoleso.ru/interesnoe-na-jrepair-ru/kuzov/zashchita-avtomobilya-ot-korrozii

Anti-corrosion coating of a car body: types, anodic and cathodic protection against corrosion, which requires anti-rust treatment with anti-corrosion agent

Corrosion is the destruction of metal due to its chemical reaction with water and oxygen. During movement, the unprotected surface of the body and other parts is constantly exposed to mechanical stress and comes into contact with air, which contains oxygen.

Car body corrosion

Atmospheric precipitation, in turn, contributes to the ingress of moisture onto the metal, and in hard-to-reach places of the car, moisture evaporates for quite a long time. The reaction of iron with water and oxygen leads to the formation of destructive rust.

Rust is one of the most serious “diseases” of the body. Its spread leads to a weakening of the vehicle's power structure and reduces the level of passive safety in a collision.

Myth 3: Only exposed areas of the body rust, which cannot be protected with anticorrosive.

It's not like that at all. Please note that many cars rust along the lower edges of external surfaces and elements. The edges of hoods, doors, trunk lids, the edges of roof panels, the lower edges of fixed rear fenders - these are the first areas to be attacked by corrosion. Why? It's all about condensed moisture, which inevitably forms in the off-season. During night frosts, the body metal cools to low temperatures and dew falls on it.

And not only from the outside, but also from the inside - after all, the air and the moisture contained in it penetrates into all unsealed cavities. And if the dew dries on the outer panels, it does not on the inner panels. Droplets of moisture flow down to the lower edges and collect there, gradually penetrating to the steel through a thin layer of soil. As a result, rust - hydrated iron oxide - breaks out from under the paint.

Therefore, first of all, it is necessary to protect the hidden cavities of the body and the joints of metal sheets with anticorrosive agents!

Restoration of anti-corrosion and anti-noise coating of the underbody and wheel arches

During the operation of the car, the coating on the underbody is exposed to gravel, sand, salt, moisture, as a result of which the mastic and primer are damaged and erased. Exposed metal is susceptible to corrosion.

At the car plant, a layer of D-11A grade polyvinyl chloride plastic compound 1.0-1.2 mm thick using epoxy primer EF-083 is applied to the lower surface of the body base, wheel arches and side members for sound insulation and protection against corrosion and abrasive wear.

If the plastic layer is damaged without disturbing the primer layer, the damaged areas are cleaned of dirt, degreased, and plastisol is applied to the dry surface by airless spray or brush. Dry the plastisol at a temperature of 130 °C for 30 minutes.

Due to the significant difficulty of heating the body coating to a high temperature and the need to completely disassemble the car, it is possible to restore the coating by applying anti-noise mastic BPM-1, which can dry under natural conditions.

Before restoring the coating, the car is placed on a lift, the underbody is carefully inspected and coating defects are identified. Clean the bottom of the body from dirt, remove rust with a spatula, sandpaper or rust converter. Blow the bottom of the body with compressed air. Then place the car on a lift in the mastic application chamber and remove the wheels.

Cover the brake drums and discs with protective covers, insulate the cardan drive, mufflers, cables and body parts that cannot be treated with mastic with thick paper and adhesive tape. Using a rag soaked in white spirit, degrease the areas that have been stripped down to metal, apply GF-073 primer to them by spray or brush and allow to dry for 5-10 minutes.

Then BPM-1 mastic is applied to the defective areas by spraying or manually (with a brush or spatula) in a layer 1.0-1.5 mm thick. The spillage of mastic onto adjacent areas that are not damaged should be minimal. In the cold season, the mastic is kept in a warm room before use. If the mastic is contaminated, it is diluted with xylene (no more than 3%).

If the paintwork on the front panels is contaminated with mastic, clean it with a rag soaked in white spirit. Dry the mastic at a temperature of 18-20°C for at least 24 hours. To speed up drying, keep the coating at a temperature of 100-110°C for 30 minutes.

Algorithm of actions

We detect traces of corrosion

Source: https://AutoManya.ru/sovety/zashchita-kuzova-avto-ot-korrozii.html

Top products for anti-corrosion treatment of car bodies

The durable metal surface of new or old cars is coated with special anti-corrosion agents. This allows, under conditions of constant use, to extend the service life of the car body for a long time.

The production volumes of anti-corrosion coatings continue to grow because all means cannot protect even the highest quality car from the oxidative effects of air, water and time. With a skillful approach and regular care of the condition of the car, when applying an anti-corrosion coating to the car, careful car owners can manage to keep the car untouched by rust for a significant period of time.

How to protect your car from corrosion

Anti-corrosion treatment of a machine requires the use of several substances and technologies. During the complete rust treatment procedure, the following types of protection are used:

Protective anti-corrosion substances that actively interact with the surface of the machine and repel moisture, for example, Movil with a corrosion inhibitor.

Refers to mechanical methods of protection. Substances are also used that, after applying a thick layer to the surface of the car, completely isolate the car from corrosion or external influences of sand and gravel. For example, mastics have good protective properties against mechanical damage and corrosion.

Products that transform the surface of a car that has already begun to rust. They cover up rust on the body.

They combine several substances into a single complex.

The first type of anti-corrosion treatment for a car is done with your own hands to prevent corrosion on the bottom of the car. To provide passive protection to the underbody, it is carefully covered with a special material, thus preventing the lower surface from getting destructive fractions from the outside.

Barrier protection and galvanizing method

Anti-corrosion protection of the car body by galvanizing is carried out at the factory.

To protect against corrosion, the machine body is dipped into a special bath of molten zinc, as a result of which a strong ferro-zinc (Fe + Zn) alloy with a layer thickness of 0.8-2 microns is formed on the treated surface.

In this case, the distribution of zinc throughout the metal of the body is as follows: in the depth of the anti-corrosion protection there is about 70% of zinc and only closer to the surface the zinc content increases to almost 100%.

After properly galvanizing, the machine is closed to corrosion barrier and electrochemically. The car body is also protected by attaching shields, hood spoilers made of plastic material or leather, as well as lockers, that is, plastic fender liners, linings, covers for the sills and the lower part of the doors.

Body lamination

Lamination is the covering of a car body with a special polyurethane, vinyl, anti-gravel film using special tools.

This anti-corrosion film not only acts as a barrier to small fractions (pebbles) falling on the car, from scratches, chips and other minor damage, but also prevents sunlight from spoiling the color saturation of your car.

This type of protection of the car body from corrosion does not damage the varnish (paint) and does not enter into a chemical reaction with the paintwork, so it can be easily removed when worn. Properly glued film lasts about five to seven years.

Cathodic protection

The effect of anti-corrosion protection when using cathodic protection devices is compared with galvanizing. The principle of operation is the polarization of the metal during the creation of a galvanic couple: the electrode and the protected surface. During the application of cathodic protection, a negative potential of the desired limit value is produced, which prevents oxidation.

The peculiarity of this method is that it protects the car from corrosion even in hard-to-reach places. Moreover, restoration of car parts already affected by corrosion becomes available. Cathodic anti-corrosion protection is also actively used to protect the trunk of a car from external influences.

How are the external surfaces of the body and muffler treated?

According to the variety of compositions of various means for treating a car body against corrosion with your own hands, you can select the following substances:

• Anti-corrosion mastic for cars.

Various tread or protective preparations, which are made on the basis of bitumen, epoxy or synthetic resin, sometimes with the addition of rubber, are applied to almost any part of the body. They have sound insulating properties, dampening resonant vibrations of the body. Mastics are applied mainly in a warm, heated form.

It is used as a protective agent with high permanent elasticity, however, such mastic does not protect against impacts and sudden movements of the machine.

• Bitumen mastic or bitumen-rubber.

A preventive agent for treating the car body against corrosion, which contains special inhibitors.

Suitable not only for anti-corrosion treatment of external parts of the car, but also for coating the bottom of the car.

Contains elements of different types of mastic and can withstand air temperatures reduced to -60 C.

Polymer liquid anti-corrosion materials (sometimes phosphate), applied to the surface being treated, consist of substances based on polyvinyl chloride or rubber. This anti-corrosion treatment for cars has good adhesion, that is, excellent and durable adhesion to the surface. Apply on a pre-coated primer.

It is a polymer plastic material that is used to treat the most vulnerable areas for corrosion on a car. These are wheel arches, sills, the edge of the hood; liquid plastics are considered additional protection.

The anti-corrosion agent is designed to protect joints, seams and surfaces of the car body. After application and drying, it forms a waxy protective anti-corrosion layer.

Next you need to figure out how to paint the muffler. Protective body painting will help you in this matter. Such protection against car corrosion prevents rust and aging of the metal material. It is advisable to paint the muffler using heat-resistant paint so that the car can be used in hot and cold weather.

The highest temperature point at which protective paint performs its functions is 400 C. To increase the protective-repellent properties of the coating applied to the muffler, you can also choose paint with the addition of silicone.

Anti-corrosion agents for the muffler and other car parts require drying or heat treatment, that is, measures that increase the tightness and strength of metal parts.

Now you have learned how to protect your car from corrosion. To do this, use special car products and films glued to the body.

Source: https://InfoKuzov.ru/material-instrument/antikorrozijnnie-pokritiya

Protecting metal products from corrosion: ways to protect metal from rust at home, choosing a coating

Intensive development of steel production, as a rule, involves the search for new means and methods that would prevent the destruction of metal products. The creation of innovative techniques related to corrosion protection is an ongoing process. Products made from almost any metal can lose their performance due to exposure to chemical and physical factors from the outside. The consequences of this can be seen in the form of rust.

Types of corrosion

Before you protect metal from rust, you should find out about the existing types. The method of providing anti-corrosion protection is directly dependent on the conditions of use of the parts. Therefore, it is customary to distinguish the following types:

• corrosion, which is associated with atmospheric phenomena;
• destruction of the metal structure in water due to the presence of salts and bacteria in it;
• destructive processes occurring in the soil (soil corrosion).

Methods of anti-corrosion protection must be selected individually, based on the conditions under which the metal product will be used.

As for the types of structural damage, they can be as follows:

• rust is found on the entire surface of the product in separate areas or as a continuous coating;
• has the appearance of spots and penetrates deep into the element;
• destroys metal molecules, leading to cracks;
• large-scale rusting, which destroys not only the surface, but also deeper layers.

Types of destruction can also be combined. In some situations, they are very difficult to identify by eye, especially with spot rusting.

It is customary to emit chemical corrosion. Upon contact with petroleum products, alcohols and other aggressive substances, a special reaction occurs, which is accompanied by high temperature and gas emissions.

During electrochemical corrosion, the surface of a metal alloy comes into contact with water (electrolyte). In this case, diffusion of the material occurs. The electrolyte causes an electric current to occur, and the electrons of the metal are replaced and begin to move, resulting in rust.

Providing corrosion protection and smelting steel products are two interrelated things. Corrosion causes significant damage to commercial or industrial buildings. In addition, this process can lead to disaster, if we talk about, for example, power poles, bridges, barriers, etc.

Corrosion protection in industry and home

It is necessary to provide the metal with reliable protection against corrosion. All conditions where protection of metals from corrosion is required can be briefly divided into industrial and household.

In industry, there are several options for anti-corrosion protection:

1. Passivation. During the production process, other metal alloys (molybdenum, nickel, niobium) are added to steel. These materials are characterized by excellent performance properties and high resistance to aggressive influences. These varieties are commonly called alloyed.
2. Application of some other metals to the surface of steel. In this case, a protective coating is formed on the product. Aluminum, cobalt and chromium are often used for this purpose.
3. Use of special protectors and anodes. When a part comes into contact with water, the protector, which forms a protective coating, is destroyed. This technique is often used in the production of parts for offshore drilling rigs and ships.

Industrial methods of providing anti-corrosion protection are very diverse. These include coating with special fiberglass enamel, chemical protection, and many others.

Anti-corrosion protection of materials at home involves the use of paint coatings and chemicals. The protective properties are provided by a combination of different elements: silicone-based resins, inhibitors, polymers, metal shavings and powder.

It should be noted that before painting a part, it must be treated with a special corrosion converter or primer, otherwise its performance properties will quickly decrease.

Today there are several types of rust converters on sale:

1. Primers. They are characterized by high adhesion to metal surfaces and help level the coating before painting. Many primers contain inhibitors that slow down corrosion processes. In addition, applying a layer of primer in advance saves on painting costs.
2. Chemicals. They convert iron oxide into safer substances that are not susceptible to corrosion. Such agents are called stabilizers.
3. Compositions that convert rust into ordinary salts.
4. Oils and resins that seal and bind rust, ensuring its neutralization.

Experts advise choosing paint and primer from one manufacturer so that their chemical composition does not differ much.

Paints for coating metal products

Paints intended for treating metal surfaces are standard and heat-resistant. In most cases, three types of compounds are used: epoxy, acrylic and alkyd. There are also special anti-corrosion paints that have the following advantages:

• effectively protect the coating from atmospheric influences and temperature changes;
• can be easily applied with a roller, brush or spray;
• many of them are quick-drying;
• have a wide selection of colors;
• are durable.

As for the most inexpensive and accessible means, then you should pay attention to ordinary silver. This coating contains aluminum powder, which forms a protective film on the product treated with it.

Stages of work to combat corrosion in everyday life

Methods of combating metal corrosion require a certain sequence. The main stages of this work should be listed:

1. Before applying the converter or primer mixture, the surface must be completely cleaned of oil stains, traces of corrosion and various types of contaminants. For these measures, you can use a grinder or brushes with metal bristles.
2. After this, you can begin to apply a layer of primer, which should then be absorbed and dry properly.
3. Next, a couple of layers are applied to the surface. Before applying the second layer, you need to wait until the first one is completely dry. While working, be sure to use safety glasses, gloves and a special respirator, since all substances and compositions used are toxic.

Anti-corrosion protection of metal alloys is a very difficult process. In industry, it begins at the stage of steel melting. Manufacturers of paint coatings are improving their products, increasing their durability and resistance.

Source: https://obrabotkametalla.info/splavy/zashhita-metallicheskix-izdelij-ot-korrozii

Methods of corrosion protection and their comparison

Corrosion causes huge losses to people every year. Therefore, as soon as a person began to use metals, he immediately began to search for effective ways to protect against corrosion.

At their core, all methods of corrosion protection used today can be divided into 3 types:

• Constructive; 
• Passive;
• Active.

Constructive methods are the protection of corroded metals with various barriers, protective panels, rubber gaskets, bitumen or any other non-thin-layer coatings.

Passive methods (barrier) are primers, paints, varnishes and enamels, coatings that create a barrier aimed at isolating the metal surface from interaction with the environment.

Active methods - consist of increasing the electrode potential of the metal or using another metal, more active, which will donate its electrodes and destroy itself, thereby protecting the metal product from rust.
  Today, the most convenient and effective way is precisely this - the use of a self-sacrificing metal, and the metal that is preferred for this is zinc.

Pros and cons of corrosion protection methods

There are very few advantages to constructive methods of corrosion protection. They are difficult to use, expensive, take up a lot of space, and sometimes they are simply impossible to use. For example, as protection against corrosion of equipment, forged products, fences, and urban infrastructure. Therefore, constructive methods are used very rarely today and only where they are hidden - for internal metal structures of buildings.

Passive methods of corrosion protection have many advantages, but are not without disadvantages.

Pros:

• Ease of application
• Low price
• Variety of colors and types
• Creating a barrier between the metal surface and the environment

Minuses:

• Durability – 1-3 years under favorable conditions
• Weak resistance to mechanical damage
• Even with a small scratch, the barrier is broken, environmental manifestations penetrate the metal surface and the corrosion process begins

The most common active method of corrosion protection is galvanizing. Since protection with zinc is the most effective and durable protection of metals from corrosion. Zinc corrodes 3 times slower than most metals, and it is also much cheaper than, for example, platinum, which is also almost not susceptible to corrosion. This is why zinc is an ideal choice as a protective metal that sacrifices itself to protect other metals from corrosion.

Pros:

• Durability – protects up to 25-50 years
• High resistance to mechanical damage, aggressive environments, water and other influences
• Even if the integrity of the layer is damaged, it continues to protect against corrosion
• Allows you to add layers and increase the protection period during operation

Minuses:

• Careful surface preparation and strict adherence to the technological process are required  

Important! However, in order for zinc to work properly and protect metals from corrosion for more than 25 years, it is not enough to simply add it to paint. Several conditions must be met: zinc in the dry coating film is more than 95%. The presence of a binder and neutral resins that help zinc particles actively interact with each other and donate electrons to fight corrosion. The size of zinc particles is 12–15 microns and their purity is 98%.

If all the above conditions are met, then the zinc coating protects in two ways: passive and active. That is, it simultaneously creates a strong barrier between the metal surface and the environment, and if the barrier is damaged, it donates its electrons to corrosion until the coating is completely depleted.  

Only in this case, the resulting composition is galvanized and can be applied as a protective coating to other metals in various ways. There are several ways to apply galvanizing: hot galvanizing, cold galvanizing, galvanic, gas-thermal, thermal diffusion. You can read more about the different types of galvanizing, their pros and cons in the article: Types of galvanizing of metals.
 

Comparison of the most popular methods of corrosion protection

Characteristics	Cold galvanizing (Barrier-zinc)	Hot galvanizing	Dye
Active cathodic protection	+	+	—
Easy on-site application	+	—	+
Repeated application	+	+	—
Finish coating possible	+	±	+
Application under extreme conditions (high humidity and low temperature)	+	—	—
Unlimited shelf life	+	—	—
Contact with drinking water	+	+	—
Temperature and mechanical stability	+	+	—
Welding on coating	+	±	—
Coating restoration	+	—	—
Application at negative temperatures (-35)	+	—	—

If we compare the most popular methods of corrosion protection today, it is obvious that cold galvanizing has more advantages. Processing by cold galvanizing will allow you to save money, increase the cost of your structures, and therefore your income, and make products more attractive to your customers. Cold galvanizing will allow you to be proud of your products and not worry about their quality, because after application you can simply forget about corrosion for up to 25 years or more.

On our website you can find zinc-containing primers for cold galvanizing that can protect metal under various operating conditions. Among them, Barrier-Grunt is a zinc-containing paint-primer for metal (96% zinc) that guarantees anti-corrosion protection for a period of 10 to 50 years.

Have questions about choosing a composition? Contact the representative office in your city:

in St. Petersburg: (812) 603-41-53, (921) 927-58-47
in other cities: 8 (800) 707-53-17
e-mail: [email protected]

Source: https://terazinc.ru/antikorroziunaya_obrabotka_svoimi_rukami/sposobi_zashity/

How to defeat rust: the main ways to protect metal from corrosion

The development of the steel industry is inextricably linked with the search for ways and means to prevent the destruction of metal products. Protection against corrosion and the development of new techniques is a continuous process in the technological chain of production of metal and products made from it. Iron-containing products become unusable under the influence of various physical and chemical external environmental factors. We see these consequences in the form of hydrated iron residues, that is, rust.

Types of corrosion

Methods for protecting metals from corrosion are selected depending on the operating conditions of the products. Therefore it stands out:

• Corrosion associated with atmospheric phenomena. This is a destructive process of oxygen or hydrogen depolarization of a metal. Which leads to the destruction of the crystalline molecular lattice under the influence of a humid air environment and other aggressive factors and impurities (temperature, the presence of chemical impurities, etc.).
• Corrosion in water, primarily sea water. In it, the process goes faster due to the content of salts and microorganisms.
• Destruction processes that occur in the soil. Soil corrosion is a rather complex form of metal damage. Much depends on the composition of the soil, humidity, heating and other factors. In addition, products, for example, pipelines, are buried deep in the ground, which makes diagnostics difficult. And corrosion often affects individual parts pointwise or in the form of ulcerative veins.

Types of corrosion protection are selected individually, depending on the environment in which the metal product being protected will be located.

Typical types of rust damage

Methods for protecting steel and alloys depend not only on the type of corrosion, but also on the type of destruction:

• Rust covers the surface of the product in a continuous layer or in separate areas.
• It appears in the form of spots and penetrates pointwise into the depths of the part.
• Destroys the metal molecular lattice in the form of a deep crack.
• In a steel product consisting of alloys, destruction of one of the metals occurs.
• Deeper extensive rusting, when not only the surface is gradually damaged, but also penetration occurs into the deeper layers of the structure.

The types of damage can be combined. Sometimes they are difficult to determine immediately, especially when point destruction of steel occurs. Corrosion protection methods include special diagnostics to determine the extent of damage.

They produce chemical corrosion without generating electrical currents. Upon contact with petroleum products, alcohol solutions and other aggressive ingredients, a chemical reaction occurs, accompanied by gas emissions and high temperature.

Galvanic corrosion is when a metal surface comes into contact with an electrolyte, specifically water from the environment. In this case, diffusion of metals occurs. Under the influence of the electrolyte, an electric current arises, the replacement and movement of electrons of the metals that are included in the alloy occurs. The structure is destroyed and rust forms.

Steelmaking and its corrosion protection are two sides of the same coin. Corrosion causes enormous damage to industrial and commercial buildings. In cases with large-scale technical structures, for example, bridges, power poles, barrier structures, it can also provoke man-made disasters.

Metal corrosion and methods of protection against it

How to protect metal? There are many corrosion methods for metals and ways to protect against it. To protect metal from rust, industrial methods are used. In everyday life, various silicone enamels, varnishes, paints, and polymer materials are used.

Industrial

Protection of iron from corrosion can be divided into several main areas. Methods of protection against corrosion:

• Passivation. When producing steel, other metals are added (chromium, nickel, molybdenum, niobium and others). They are distinguished by increased quality characteristics, refractoriness, resistance to aggressive environments, etc. As a result, an oxide film is formed. These types of steel are called alloyed.

• Surface coating with other metals. Various methods are used to protect metals from corrosion: electroplating, immersion in a molten composition, application to the surface using special equipment. As a result, a metal protective film is formed. Chromium, nickel, cobalt, aluminum and others are most often used for these purposes. Alloys (bronze, brass) are also used.

• The use of metal anodes, protectors, often made of magnesium alloys, zinc or aluminum. As a result of contact with the electrolyte (water), an electrochemical reaction begins. The protector breaks down and forms a protective film on the surface of the steel. This technique has proven itself well for underwater parts of ships and offshore drilling rigs.

• Acid etching inhibitors. The use of substances that reduce the level of environmental impact on metal. They are used for preservation and storage of products. And also in the oil refining industry.

• Corrosion and protection of metals, bimetals (cladding). This is coating steel with a layer of another metal or a composite composition. Under the influence of pressure and high temperatures, diffusion and bonding of surfaces occurs. For example, well-known heating radiators made of bimetal.

Metal corrosion and methods of protection against it used in industrial production are quite diverse, such as chemical protection, glass enamel coating, and enameled products. Steel is hardened at high temperatures, over 1000 degrees.

Source: https://GidPoKraske.ru/spetsialnye-materialy/rzhavlenie/zashchita-ot-korrozii.html