Chemical metallization: technology, execution at home

The issues of effective protection and decorative design of the surfaces of products made of various materials are quite relevant both for manufacturers and for many home craftsmen. Chemical metallization, which you can do yourself, allows you to effectively solve such problems.

Chemical metallization technology can be used on virtually any hard surface

Benefits of technology

Chemical metallization is a very simple process.
Applying the coating is technologically simple. To do this, it is enough to have standard sprayers. This allows you to coat any product: from a phone case to a car hood or a statue. Any materials can be chrome-plated: plastic, ceramics, wood, plaster, etc. The degree of reflection of the coating depends on the number of layers applied. Chemical metallization gives the product additional strength and hardness. Moreover, the coating has high wear resistance. The strength here is ensured by a protective varnish that can withstand any operational wear. For the chrome plating process, dimensions do not matter. Any surface area can be sprayed in a short time. This is one of the main differences from the vacuum metallization process or galvanic electrodeposition.

Chemical coating is much cheaper than other methods. Average savings are up to 30%. In addition, the coating is environmentally friendly. In the same galvanic process, metallization occurs using toxic hexavalent components. When chrome plating, you can choose any coating color. To do this, just add a little toner to the protective varnish.

Necessary equipment

Only a potential suicide can carry out chrome plating in the kitchen of a residential apartment.
In order to begin the process of chrome plating a headlight, you must have a special room for this, as far away as possible from residential buildings. A spacious workshop or garage is best suited for these purposes. Good forced ventilation is a must. All containers with gasoline, paints, varnishes and other solvents must first be removed from the premises. It is mandatory to purchase a good fire extinguisher and consider an option for an emergency exit from the premises in the event of an emergency. For chrome plating you must have:

• Galvanic bath. Either glass or durable plastic that can withstand temperatures up to 100 degrees.
• Rectifier. Constant current source with the ability to regulate the output voltage. Parameters - 12V/50A. If we are talking about small parts, then you can use a car battery charger.
• Heater. Must withstand long-term exposure to an aggressive acidic environment. For example, a ceramic heating element. An ordinary heating element will not work.
• Thermometer. With divisions from 0 to 100 degrees. The optimal temperature for the process is 45−55 degrees.

Plastic chrome plating process

Chrome plating is the procedure for obtaining mirror surfaces by spraying chemical components onto a plastic, glass, wood or metal base. This process is popular among car enthusiasts as it helps give plastic parts a more aesthetically pleasing appearance.

Chrome-plated elements of car bodies and motorcycles, bathroom and kitchen accessories, decorative items and exterior cladding parts of houses are becoming more in demand every year. You can chrome plating plastic elements at home using auxiliary tools.

Chrome plating of plastic parts is used for decorative purposes. Thanks to chrome plating, minor damage to the surfaces of the base material is hidden and its characteristics are improved. The following properties are optimized:

Purposes of metallization of plastics

• resistance to negative environmental influences;
• hardness of the base material;
• resistance to high temperatures;
• wear resistance;
• attractive appearance.

The chemical chromium plating process requires a careful and responsible approach to safety.

The work area at home should be well ventilated, because during chrome plating there may be chemically active elements in the air that can harm health. A garage or, in the summer months, an outdoor shed, as well as an open veranda with a roof, is suitable as a room for chrome plating. As a last resort, you can use the balcony.

Direct contact with the skin of the reagents used during chrome plating can lead to serious chemical burns. In addition, poisoning of the body is not uncommon.

Preparatory work

To perform chrome plating, you need a galvanic apparatus, which you can assemble yourself.

1. You need to choose a brush with thick bristles.
2. Then the bristles and handle are removed, and the membrane of the brush is wrapped in lead wire.
3. Next, a handle with a hollow plexiglass body is made and installed on the brush. This will allow the brush to be filled with electrolyte.
4. The current source should be a powerful transformer, to which the anode and cathode will be connected (you can use a car battery, but there will be no diode in the circuit).
5. A diode is connected to a special brush made earlier, and the anode is connected to a cable leading to the step-down winding of the transformer.
6. The cathode is installed on the element that needs to be chrome plated.
7. Then a container for chrome plating is installed and a special composition is prepared with equal proportions of caustic soda, soda ash, silicate glue and water. The solution is thoroughly mixed and brought to a boil.
8. The part that must undergo the chrome plating process is placed in a ready-made degreasing solution.
9. A special electrolyte is prepared using chromic anhydride, sulfuric acid and water.
10. Before you start chrome plating plastic yourself, you need to change into overalls, protect the skin of your hands, eyes and respiratory organs with special means (goggles, rubber gloves, respirator).

The main problems with chrome plating and methods for solving them

1. Lack of coating in recessed areas of the product - occurs due to low current density in recessed areas and excess sulfuric acid in the electrolyte.

Solution: use shaped anodes, start the chrome plating process (1-2 minutes) at twice the current density - give a boost to the current, reduce the sulfuric acid content - add water or chromic anhydride to the electrolyte.

1. The coating is matte or burnt (usually on protruding parts of products) - occurs due to high current density at a given temperature, passivation of anodes or insufficient heating of parts before the process.

Solution: adjust the ratio of current density and temperature, increase the distance between the anodes and cathodes, clean the anodes, control the heating of the parts before immersing them in the chrome plating bath.

1. Dark stains, stripes, dots on the surface of products - insufficient concentration of sulfuric acid in the electrolyte solution

Solution: add sulfuric acid to the solution.

1. The dark color of the coating means a high content of trivalent chromium, a lack of acid, and a low temperature of the electrolyte during the chrome plating process.

Solution: in addition to heating the electrolyte and adding sulfuric acid, the electrolyte should be treated with current.

1. The coating peels off - poor-quality degreasing of the product surface, a sharp increase in current density with decreasing temperature.

Solution: adjust the temperature regime of chrome plating, improve the preparation of the surface of the product.

1. Graininess or swelling - the presence of solid particles in the electrolyte and (or) poor preparation of the product for galvanic processing.

Solution: electrolyte filtration and quality control of parts preparation.

Application area

The electric arc metallization method in combination with subsequent painting of metal structures is a hybrid coating, the service life of which significantly exceeds the sum of the service life of each layer separately due to the synergy effect. Such coatings are used for long-term anti-corrosion protection of products operated under conditions of exposure to aggressive factors inside and outside structures, in liquids. Coatings formed as a result of electric arc metallization are used to protect:

• metal structures;
• reinforced concrete supports of overpasses, bridges;
• fuel and oil storage facilities;
• pipelines;
• equipment for petrochemical industry enterprises, heating networks.

Three parts of the galvanic process

Electroplating at home, chrome plating is an electroplating process. Therefore, to carry it out, it is necessary to have three components: a cathode, an anode and an electrolytic medium in which the transfer of charged metal particles will occur.

• Cathode. A plate of pure lead or an alloy of lead and tin. It must be remembered that the cathode area must be larger than the anode area. The cathode is connected to the positive output of the rectifier.
• Anode. This is the chrome-plated part itself. It should hang in the electrolyte medium so as not to touch the walls and bottom of the container. In addition, the anode must never touch the cathode.
• Electrolyte. Chromium plating requires particularly careful preparation of the electrolyte.

Electrolyte preparation

The electrolytic fluid kit for chrome plating includes the following components:

• Chromic anhydride: 250 g/l.
• Sulfuric acid: 2−3 g/l. Chemically pure, concentrated. Technical sulfuric acid is not suitable.
• Distilled water.

The water is heated to a temperature of 60−80 degrees. After this, the anhydride dissolves in it. The solution is cooled slightly and then the required amount of sulfuric acid is added to it in a thin stream.

Preparing the surface of a chrome-plated product

Consists of three stages:

• Mechanical cleaning, grinding and polishing.
• Degreasing.
• Nickel plating.

The peculiarity of chrome plating is that, on the contrary, it emphasizes all existing irregularities, chips and cracks on the surface of the product. Therefore, traces of old paint, rust, chips, cracks and other defects must first be removed from the surface of the chrome-plated part. Preparation of the chrome surface consists of the following steps:

• Sandblasting.
• Polishing with fine sandpaper.
• Sanding with soft materials and polishing paste.

Do not use gasoline or White Spirit for degreasing. Otherwise there will be problems with the quality of chrome plating. The best option is to prepare a special solution:

• Caustic soda: 150 g/l;
• Soda ash: 50 g/l;
• Silicate glue: 5 g/l.

The solution is heated to 90 degrees. After that, the part is lowered into it and kept for 20-40 minutes, depending on the area and surface relief of the part.

Nickel plating is the last stage of preparing a part for chrome plating. The nickel plating process is carried out in a special galvanic bath. The cathode in this case is metallic nickel, and the electrolyte is a solution of sulfuric acid and nickel salts.

Removing poor-quality coating

There are two ways to remove low-quality chrome. The first is chemical dissolution, carried out in a 50% solution of sulfuric acid. The products are placed in a container with sulfuric acid and kept until the coating is completely dissolved. The second is the anodic dissolution method, carried out in a galvanic bath. Products are immersed in a bath of 20% caustic soda solution and connected as an anode; steel sheets or parts are used as a cathode. The process takes place at a temperature of 70-80C and an anodic current density of 20-25 A/dm2 until chromium is completely dissolved. Before repeated chrome plating, the products are heated for 1.5 hours at a temperature of 150-200C to remove hydrogen.

Usage

The use of chromium in ferrous metallurgy is large - it is about 2/3 of the total metal smelting. The production of chrome-plated alloys is profitable - even small additions of alloys give the alloy the best qualities of a resistant metal.

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The remaining third is mainly used for chrome plating. Chrome plating can be functional, decorative, or combine both qualities.

Chrome wheels

Plumbing products are simply designed for chrome plating. Heat, moisture, and chemicals will not damage the faucet, shower, or bathroom accessories.

Informative: often the protective layer is applied to a previously created “primer” of copper and nickel.

A layer of functional chrome plating protects parts from corrosion; its thickness reaches several millimeters.

Decorative chrome plating is for beauty; its layer is thin, only 0.2-0.7 microns.

Chrome plating happens:

• electrolytic;
• chemical;
• vacuum;
• diffuse.

Interesting: a gas plasma spraying method has been developed that makes the chrome plating process safe.

Chemical metallization at home

If you decide to do chemical metallization yourself, you should not only study the theoretical material, but also watch a training video on this topic. Naturally, it is necessary to prepare a set of equipment and consumables to carry out this technological process.

For chemical metallization, chemical reagents that are hazardous to health are used, and when working with them, safety requirements must be strictly observed. The technology of chemical metallization itself, as mentioned above, is not particularly difficult and resembles conventional painting. The main thing is to strictly adhere to a certain sequence of actions. You can learn more about this technique in videos that are easy to find on the Internet.

The simplest installation for chemical metallization may consist of an enamel container and a blowtorch. To perform the treatment, you will need the appropriate reagents and knowledge of chemistry to mix them correctly. Having studied the theoretical material, watched the corresponding video and prepared your apparatus for chemical metallization, you can proceed to the metallization itself.

The algorithm of actions in this case is as follows:

1. Carry out thorough cleaning of the treated surface from contaminants.
2. Perform degreasing. This stage should be approached very responsibly, since the characteristics of the applied coating largely depend on the quality of its implementation. This procedure can be carried out using an alkaline solution or a high-quality detergent, which allows you to remove all organic contaminants from the surface of the product.
3. Wash the grease-free surface with water.
4. If not the entire product is subjected to chemical metallization, then those areas of it that will not be coated must be insulated with lead that is resistant to the effects of an electrolytic solution.
5. The product is attached to a wire through which electric current will be supplied to it, and lowered into a container with an electrolytic solution. The product should be kept in this solution for an hour.
6. The treated product is removed from the solution, dried, cooled and, if the quality of the applied coating is high enough, polished.

At home, you can use a mini-installation for chemical metallization, powered by a compressor

In order to obtain a high-quality metal layer on the surface being treated without harming your health, you should follow certain recommendations.

• Before starting the procedure, you need to check the reliability of all electrical contacts that will bear the main load.
• When performing all stages of chemical metallization (especially when removing the workpiece from an electrolytic solution), you should use rubber gloves that will protect the skin of your hands from chemical and thermal burns.
• The room in which chemical metallization is performed must be well ventilated. This requirement is explained by the fact that when this procedure is performed, intense gases are released and fog is formed, which irritates the mucous membranes of the respiratory and visual organs.
• When performing chemical metallization, it is advisable to use a respirator and safety glasses.

Metallization using standard spray equipment

In general, if you properly prepare for chemical metallization, carefully study all the theoretical aspects of this process and watch the corresponding video, then as a result you can obtain high-quality decorative coatings that also have excellent protective properties. Using this technology, even at home you can make various decorative products, restore the surfaces of worn parts, and apply a coating to them that protects them from the negative influence of the external environment.

Various processing technologies can be used to protect fragile materials and decorate them. Chemical metallization is a process that involves the formation of a thin protective layer on a surface of various shapes. This technology has a large number of features, which we will discuss in more detail later.

Course of action

To do chrome plating at home using a special galvanic brush, you can use the following procedure:

1. The fibers are tightly wrapped with lead wire.
2. The wrapped bristles are placed in a transparent cylinder (preferably made of plexiglass). The top of the container is covered with a lid equipped with a filling hole and a metal contact. One of the ends of the lead winding made is soldered to this contact.
3. Small through holes need to be made in the foam plastic membrane located above the bristles.
4. A 12-watt transformer is used as a rectifier. The plus is supplied to the contact, which is attached to the cover, the minus is fixed on the element being processed.
5. The electrolyte contained in the cylinder penetrates the bristles through holes made in the membrane.

When using any method, a compressor or a good vacuum cleaner will be useful to remove dust.

Electrolyte preparation

To calculate the volume of electrolyte ingredients, you should adhere to the following ratios, measured in grams, per liter of pure water:

1. Chromium anhydride - 250 g;
2. Sulfuric acid - 2.5 g.

A glass vessel is filled halfway with settled and boiled water, the temperature of which should be approximately 60 degrees. Chromic anhydride is then placed into the container. The solution is stirred until the substance dissolves, after which sulfuric acid is carefully poured into it.

Then the composition must be kept under current for three and a half hours. If the calculations are made correctly, the electrolyte will turn dark brown. Having de-energized the composition, it must be left for one day in some cool and dark place.

Part preparation

Before you do chrome plating yourself at home, you need to prepare it. Rust, varnish, dirt and paint must first be removed from surfaces to be treated. Once the cleaning is complete, you can begin degreasing.

Experts point out that it is undesirable to use gasoline and white spirit for this purpose, because these compounds will negatively affect processing. It is better to use a special mixture based on caustic soda, soda ash and silicate glue

The solution must be heated to 90 degrees Celsius and the part should be immersed in it for about half an hour. If the element has a complex configuration, then the holding time can be increased.

Preparation for the procedure

Due to its simplicity, chemical chrome plating does not require significant financial costs. It is not difficult to perform chrome plating at home using this technology; to do this, it is enough to carefully study the theoretical material and watch the corresponding video.

During the chemical chrome plating process, contact of solutions with unprotected areas of the body should be avoided.

Such chrome plating at home should only be carried out in non-residential premises in which effective ventilation is organized. In addition, it is necessary to use personal safety equipment:

• a respirator that protects the respiratory system;
• glasses for eye protection;
• gloves, clothing and shoes that protect the skin;
• oilcloth apron.

Solutions for chrome plating, performed using chemical technology, as well as for carrying out all auxiliary technological operations, are prepared on the basis of distilled water. The reagents used in this case must be marked with the letter “C”, which indicates their chemical purity. The containers in which working solutions are prepared can only be glass or enamel.

Reagents for chemical chromium plating

Before chemical chrome plating, the surface of the product should be thoroughly cleaned and degreased. The reliability and quality of chrome plating are largely determined by the thoroughness of these procedures. If the surface to be treated is sufficiently dirty and there are remnants of the old coating or traces of corrosion on it, then it is treated using a sandblasting machine or emery cloth, achieving a metallic shine. Preliminary grinding and polishing of the product allows you to create a more reliable and high-quality chrome coating. After performing these technological procedures, the surface to be treated is degreased using an aqueous solution containing the following components:

1. caustic soda – 100–150 g/l;
2. sodium carbonate – 40–50 g/l;
3. liquid glass – 3–5 g/l.

Washing and degreasing parts before chrome plating

To perform degreasing, the resulting mixture is heated to 60–100° and only after that the product being treated is lowered into it. Depending on the degree of surface contamination, the product is kept in a heated solution from a quarter of an hour to 60 minutes. To improve the adhesion of chromium to the surface being treated, you can additionally perform pickling, which is carried out in a solution of hydrochloric and sulfuric acids.

If it is necessary to perform chemical chromium plating on aluminum, a product made of this metal is also subjected to zincate treatment, after which it is washed. Before chemical chrome plating of steel alloy parts, a layer of copper is first applied to their surface. For this, an aqueous solution is used, including the following components:

1. copper sulfate – 50 g/l;
2. concentrated sulfuric acid – 5–8 g/l.

The operating temperature of such a solution, in which the product is kept for several seconds (5–10), should be 15–25°. After exposure to the copper plating solution, the product is washed with water and dried. If the steel after copper plating is additionally coated with a nickel layer, the thickness of which will be about 1 micrometer, then the chrome plating performed in the future will be of higher quality.

Chrome plating of parts: step-by-step instructions

Chrome plating technology is not particularly complicated.

In order to prepare electrolyte for a small product, you need to take an ordinary glass jar of the required size or a plastic bucket and place it in a special tank. For these purposes, you can use a can. For electrolysis to be of high quality, it, the can, must be thermally insulated. Namely, take a wooden box or box, insulate it with fiberglass or polystyrene foam, as well as additional mineral or glass wool, sand and place the tank there.

Place a heating element and a thermometer inside the tank. Cover the top with a sheet of moisture-resistant plywood, which will act as a sealing cover, and attach the electrodes. Attach the cathode to the product, and immerse the anode (rod or plate) into a container with the sample.

The part in the can must be held with a bracket to ensure chrome plating on all sides.

Preparation of electrolyte solution

To carry out chrome plating of parts at home, you need to prepare a special solution consisting of chromium anhydride (250 g per liter of distilled water) and sulfuric acid (2.5 g per liter of water).

First you need to fill half the container with heated water (about sixty degrees Celsius). Add the required amount (based on the total displacement) of chromium anhydride, stir until completely dissolved, and add water to obtain the required volume. Then add sulfuric acid, stirring the liquid.

The resulting solution must be worked for three and a half hours, passing current energy through it (about 6 A per 1 liter). When the electrolyte turns dark brown, it will need to stand for at least a day.

Sample preparation procedure

Before preparing the part, you need to heat the electrolyte solution to sixty degrees Celsius and let it stand for three hours.

During this time it is necessary:

1. Clean the part from dirt, rust, paint.
2. Carry out degreasing using a special solution, for which there are several recipes. For example, it may consist of 150 g of sodium hydroxide, 5 g of silicate glue, 50 g of soda ash. Take everything per liter of water. Mix the ingredients, heat to ninety degrees Celsius, lower the product and leave for at least twenty minutes, and sometimes longer, depending on the size and degree of cleansing.

Direct chrome plating

During the chrome plating procedure, it is necessary to maintain the temperature of the electrolyte solution at an average of 53 C° (plus or minus two degrees). Place the product in the electrolyte and after a minute, apply voltage to equalize the temperatures of the sample and solution. Remove the part and dry for at least two and a half hours

Occurrence of defects

When chrome plating at home, defects such as:

1. The surface shines unevenly. Occurs due to high current or low temperature of the electrolyte solution.
2. Lack of shine - due to incorrect amount of chromium anhydride, excessive current, lack of sulfuric acid.
3. The presence of brown spots means an excess of chromic anhydride and not enough acid.
4. The layer is uneven. Excess current.
5. Softening of the coating – high solution temperature, low current.
6. Chrome plating falls off - unstable voltage, poorly carried out dehydration, low solution temperature.

Chrome plating at home is a process that requires a certain skill and strict adherence to the rules and instructions. Any violation can lead to poor-quality chrome plating. Therefore, it is worth studying the technology of this process in detail and only then proceeding with its implementation.

Chemical chrome plating

Chemical metallization

Chemical metallization is the formation of a thin film of metal on the surface being treated under the influence of various chemical reagents. This method can be used to obtain coatings with zinc (zinc plating), chromium (chrome plating), aluminum (alitizing) and others. Using this technology, it is possible to obtain an even layer of metal on materials with different types of surface: smooth - glass, porcelain, polished stone, or porous: wood, plastic, gypsum.

Workplace and equipment

As a result of the chemical reaction, a gas is released that negatively affects the mucous membranes of the respiratory tract, so the process must be carried out in a room with forced ventilation or in an open space.

Equipment you will need:

• enamel bath;
• measuring cups with a capacity of 1 l and 250 ml;
• 3 bottles of 100 ml;
• disposable syringes for 5, 20, 50 ml3;
• disposable glasses of 50 ml;
• kitchen electronic scales.

Don’t forget to get rubber gloves, a respirator, sponges, and a set of protective clothing, as caution is required when working with concentrated hydrochloric acid, otherwise burns are inevitable

Reagents

Depending on the material of the workpiece and the type of coating, reagents are purchased. For chemical metallization with silver, you will need the following reagents:

• hydrochloric acid;
• silver nitrate;
• tin chloride;
• sodium hydroxide;
• ammonia;
• glucose;
• formalin;
• distilled water.

Preparation of solutions for:

• surface activation - stannous chloride, hydrochloric acid, distilled water;
• recovery - glucose, formaldehyde, distilled water;
• silvering - silver nitrate, sodium hydroxide, ammonia, distilled water.

Surface preparation

the surface is prepared in several stages. Porous and painted products are sanded, the old paint layer is removed, the surface is cleaned of dust, washed and degreased. You can degrease with white spirit, acetone or a solution of sodium hydroxide in water t= +40...+60°C. The surfaces are wiped with a sponge containing a degreasing compound, then washed with distilled water with another sponge. The prepared surface must be completely wetted with water, without dry spots - in these places defects will be inevitable.

Coating the product with an activating composition

The object to be treated is poured with tin chloride evenly over the entire surface for 1 minute, then washed with distilled water for 3 minutes.

Metallization

To obtain a uniform metal film, a solution of a reducing agent and silver plating is sprayed onto the product simultaneously and in equal volumes. Since the resulting mirror film is very thin and not durable, it can be strengthened with a protective varnish - transparent or tinted.

The described method resembles the painting process. There is another, more complex way of performing work - electrochemical metallization.

Materials and equipment used

Chemical metallization, as mentioned above, can be done with your own hands and in a home workshop. Moreover, products that are small in size and simple in shape are processed using this method even without the use of special equipment. If you have such equipment at your disposal, then you can chemically apply a layer of metal even to large parts of complex configurations.

When performing this procedure yourself, you should be extremely careful, as this involves using chemicals that are hazardous to health. If you properly prepare the equipment and materials for performing chemical metallization, then you can obtain coatings on various products with your own hands at home, the quality of which is practically no different from those formed at the factory.

Reagents for chemical metallization

The kit for chemical metallization must contain reagents that have the properties of an activator and a reducer. To perform this procedure, you will also need a primer, which is applied to the surface to be treated, and a varnish that protects the finished coating from the negative influence of external factors. To apply the final varnish coating, you should choose a material that has high hardness and wear resistance.

To color the applied metal layer in the desired color, you can use a special color toner. The primer mentioned above is necessary in order to improve the adhesion of the applied metal layer to the material from which the product being processed is made. The result of do-it-yourself chemical metallization may not always be of high quality. However, the applied coating can be removed using special removing solutions.

The chemical metallization unit is designed for coating any hard surface

Technological features of metallization

Metallization technology is produced in the following states:

• in a cold state;
• in a heated state;
• diffusion.

Products made of metal, any type of plastic, wood, glass, gypsum, concrete and other materials can be subjected to this processing method as metallization. The most common method of coating at home is spraying. Materials intended for the process can be found in stores. They are usually sold in pressurized cans with a spray nozzle.

A protective layer on metallized parts can be obtained:

• in a liquid medium;
• in a gas environment;
• using solid components.

Application of metallization coating in a cold state or heated to a low temperature is typical for the first group and subgroup 2a. During the cycle, the dimensions of the part change to the thickness of the applied layer of metals or their alloys.

Subgroup 2b is characterized by saturation of the surface layer by diffusion at high temperatures. During processing, an alloy is formed, and the dimensions practically do not differ from the specified ones.

How to determine steel grade

There are simply a huge number of different steel options, each grade is characterized by its own specific features. If the manufacturer has not carried out markings, then you can find out the characteristics of the metal only by independently conducting various tests. We'll talk about this in more detail later.

How to determine steel grade

Methods for determining steel grade

A fairly common question is how to determine the grade of steel. There are several common methods:

1. The first involves removing chips from the surface, for which a chisel can be used. At high carbon concentrations it will be short and brittle. A decrease in the indicator causes an increase in plasticity. However, it is not possible to accurately determine the brand using this method.
2. The second method involves hardening the product, after which it is necessary to make cuts. If the material is simply sawed before and after hardening, then it contains a small amount of carbon. Due to the increase in carbon concentration after treatment, the surface becomes too hard.
3. Determining the steel grade by spark is based on a visual inspection of the sparks that are formed when processing the surface with a grinding wheel. With an increase in the size of the sparks and their number, the hardness index increases, which depends directly on the carbon concentration. Such a test does not give an accurate result, since the main characteristics of the flying chips depend on the force of pressing and some other points. You can find tables that decipher the qualities of a material based on chips.

Spark test methodDevice for determining steel grade

You can also determine the brand by the color of the sparks produced. For this purpose, special tables were compiled. The test can be carried out at home only if the lighting is correct.

However, it is impossible to accurately identify the material in this way.

The option with alloying elements can also be identified by other performance characteristics, for example, resistance to high humidity or strong magnetism.

In the CIS, the applied designation standards are characterized by the fact that they can be used to indicate the main elements. When considering the issue of decoding the brand, we note the following points:

1. The abbreviation “St” is often used. In other cases, no abbreviations are used at all, only numbers.
2. In most cases, the first number indicates the carbon concentration. The following can be used to indicate the amount of alloying components.
3. The composition may include alloying components that significantly change the properties of the material. An example is the inclusion of chromium, which increases resistance to high humidity.

Classification of steels by purpose

Labeling is deciphered using tables that indicate the designation of the chemical element.

Marking of steels according to international and CIS standards

In order to decipher a brand, you can use a variety of standards. Some alloys are designated by certain symbols that indicate the purpose of the metal.

An example is the following points:

1. The letter “Ш” is used to designate metals that are used to make bearings. They are characterized by increased wear resistance.
2. High-quality alloyed workpieces are designated by the letter “L”. Often the symbol is indicated at the end.
3. “T” is used to designate heat-strengthened rolled products.
4. High corrosion resistance of the workpiece is determined by the letter “K”.
5. If copper is included in the composition, then the symbol “D” is used when indicating the brand.
6. Instrumental can be identified by the letter “U”. They are often used in the manufacture of various tools that are characterized by high wear resistance.
7. The symbol “P” is indicated to designate alloys that contain tungsten. Such a substance significantly increases the heat resistance of the structure.

By deciphering the brand, you can determine which chemical elements are included in the alloy. The numbers in most cases indicate the concentration, symbols, type of alloy and specific chemical elements.

European steel marking system Carbon steel grades according to GOST and ISO international standards

In conclusion, we note that there is simply a huge number of products on sale; in many cases, the brand is affixed by the manufacturer. It is almost impossible to independently determine the composition without the use of special equipment.

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Chrome Plating Basics

Modern technology of chemical metallization allows the use of special paints and varnishes and reagents to develop spraying. As a result, the coating will shine and reflect surrounding objects. In addition, it is chemical metallization that allows you to achieve the highest degree of adhesion

It is important that the coating process is carried out without the aid of any caustic substances or explosive components. Carcinogenic components of chrome plating are reduced to an absolute minimum

Chemical metallization has no restrictions on the shape and size of the product. There is also no need to place the item in a liquid acidic environment or resort to high heat.

Preparing the surface for chrome plating is similar to the process before applying paint. Thanks to this, mirror coatings can cover any base, but it is better if they are metallic. Such chemical treatment does not require significant cash injections. It is enough to purchase a special installation and reagents. As a result, the owner of the equipment will be able to apply a “silver mirror” even to porous or organic materials. No other technology can produce similar results. Today, chrome plating is a powerful competitor to other metallization processes.