What metal can be anodized

Steel oxidation

One of the important tasks in preserving metal structures is combating the harmful effects of the environment. High humidity and the presence of chemically active elements in the air that can destroy the integrity of metal, especially steel, lead to a deterioration in such indicators as reliability and strength.

To solve this problem, finished products are coated with various types of protective coatings.

Steel oxidation

There are various methods to improve surface stability and corrosion resistance.

One of these methods is to create a protective film on the surface of steel using special processing methods.

Understanding the essence of the purpose of this process requires an answer to the question - what is oxidation?

The essence is to use the properties of the oxidation-reduction reaction, as a result of which a protective film is formed on the surface of the steel. Steel oxidation is also carried out.

This process allows you to solve the following problems:

• Protect steel structures from corrosion (this is especially important in modern construction where metal structures are used).
• Limit exposure to aggressive components of the external environment (solutions of acids, alkalis, chemical elements that destroy the integrity of steel).
• Create a surface layer with good electrical insulating characteristics.
• Give details, individual elements, and the structure as a whole original decorative and aesthetic properties.

Metal oxidation is carried out using the following methods:

1. Using chemical reactions (chemical oxidation of steel).
2. Use of electrochemical processes (anodic oxidation).
3. Carrying out heat treatment (thermal method).
4. Creation of low-temperature plasma (plasma method).
5. Laser (special laser installations are used).

Anodized steel

Let's look at each method in more detail.

Chemical oxidation

This process involves the processing of metals with solutions, mixtures, melts of chemical elements (oxides such as chromium oxides). This oxidation allows for the so-called passivation of the metal surface. It involves the creation of an inactive (passive) formation in a metal layer close to the surface. A thin surface layer is created that protects the main part of the structure.

Technologically, this process is implemented by lowering the prepared metal part into an alkali or acid solution of a given percentage.

They keep it there for a certain time, which allows the oxidation-reduction reaction to fully occur. Then the part is thoroughly washed, subjected to natural drying, and final processing.

Chemical oxidation of steel

To create an acid bath, three types of chemically active acids are used: hydrochloric, nitric, and orthophosphoric. The acceleration of the chemical reaction is stimulated by adding manganese, potassium, and chromium compounds to the acid solution. The oxidation reaction occurs at a solution temperature in the range from 30 °C to 100 °C.

The use of solutions based on alkaline compounds allows the use of additives of sodium nitrate and manganese dioxide compounds. In this case, the solution temperature must be increased to 180 °C, and with additives up to 300 °C.

After the procedure, the part is washed and dried. Sometimes potassium bichromate is used to consolidate the chemical reaction process. To increase the shelf life of the formed film, chemical oxidation with oiling is carried out. Sometimes this process is called chemical oxidation. The final coating with oil results in a reliable anti-corrosion coating with a striking, highly decorative black color.

This type is called electrochemical oxidation of steel. Sometimes it is called anodic oxidation of steel. The term anodizing is also used. It is based on the chemical process of electrolysis. It can be carried out in both solid and liquid electrolytes. The prepared workpiece is placed in a container with an oxide solution.

The electrolysis reaction is possible by creating a potential difference between two elements.

The surface of the oxidized product is characterized by a positive potential. Chemically active elements with a negative potential are isolated from the solution. The interaction of oppositely polar elements is called the electrolysis reaction (in our case, anodization).

Anodic oxidation

The anodization reaction can be performed at home. It is required to strictly comply with safety regulations. The reaction involves harmful reactive fluids and unsafe voltage.

The use of anodic oxidation makes it possible to create protective films of various thicknesses. The creation of thick films is possible through the use of a sulfuric acid solution.

Thin films are obtained in solutions of boric or phosphoric acid. Using anodization, you can give the surface layer of metal beautiful decorative shades. For this purpose, the process is carried out in organic acids. Oxalic acid, maleic acid, sulfosalicylic acid are used as such solutions.

Micro-arc oxidation is a special anodizing process. It makes it possible to obtain coatings with high physical and mechanical characteristics. These include: protective, insulating, decorative, heat-resistant and anti-corrosion properties. In this case, oxidation is carried out under the influence of alternating or pulsed current in special baths filled with electrolyte. Such electrolytes are weakly alkaline compounds.

Anodic oxidation at home

Anodizing allows you to obtain a surface layer with the following properties:

• reliable anti-corrosion coating;
• good electrical insulators;
• thin but durable surface layer;
• original color scheme.

Anodizing stainless steel requires a special approach. This is due to the fact that such steel is considered a neutral (inert) alloy. Therefore, in production, when anodizing a large number of parts, a two-step procedure is used.

At the first stage, stainless steel is anodized together with another metal that is more suitable for this process. It may be nickel, copper, other metal or alloy.

At the second stage, the stainless steel itself is oxidized directly. To simplify the oxidation process, special additives, so-called passivating pastes, are being developed today. These compounds speed up the reaction process of stainless steel.

According to the term, oxidation occurs at relatively high temperatures. The value of this indicator depends on the steel grade. For example, the process of thermal oxidation of ordinary steel occurs in special furnaces.

A temperature close to 350 °C is created inside. A class of alloy steels undergo thermal oxidation at higher temperatures. It is necessary to heat the workpiece to 700 °C. Treatment continues for one hour.

This process is called steel bluing.

Steel bluingSteel gun after bluing

Plasma oxidation

This oxidation is carried out in an environment with a high concentration of oxygen using low-temperature plasma. Plasma is created due to discharges that occur when high- or ultra-high-frequency currents are applied.

Plasma oxidation is used to form oxidized films on fairly small surfaces.

It is mainly used in electronics and microelectronics. With its help, layers are formed on the surface of semiconductor compounds, the so-called pn junctions. Such films are used in transistors, diodes (including tunnel diodes), and integrated circuits. In addition, it is used to increase the photosensitive effect in photocathodes.

Plasma oxidation

A type of plasma oxidation is oxidation using high-temperature plasma. Sometimes it is replaced by an arc discharge with an increase in temperature to 430 ° C and higher. The use of this technology can significantly improve the quality of the resulting coatings.

Laser oxidation

This technology is quite complex and requires special equipment. To carry out oxidation use:

• pulsed laser radiation;
• continuous radiation.

In both cases, infrared laser systems are used. Due to laser heating of the top layer of material, it is possible to obtain a fairly resistant protective film. However, this method is only applicable to a small surface area.

Laser oxidation

DIY oxidation

You can organize the process of oxidation of small metal products in your home laboratory. By strictly following the sequence of technological operations, high-quality oxidation is achieved.

The whole process should be divided into three stages:

1. Preparatory stage (includes preparation of the necessary equipment, reagents, and the part itself).
2. Direct oxidation stage.
3. The final stage (removing harmful traces of the chemical process).

At the preparatory stage the following work is carried out:

• Rough cleaning of the surface (use a metal brush, sandpaper, polishing machine with appropriate discs).
• Final mechanical polishing of the surface.
• Removing grease and polishing residues. It's called decopying. It is carried out in a five percent solution of sulfuric acid. The residence time of the workpiece in the solution is one minute.
• Washing the part. This procedure is carried out in warm boiled water. It is advisable to carry it out several times.
• The final operation is the so-called passaging. After washing the part after processing, place clean boiled water in which laundry soap is first dissolved. This solution, together with the part, is heated and brought to a boil. The boiling procedure is continued for several minutes.

Oxidation at home

This concludes the preliminary stage.

The main stage of oxidation consists of the following operations:

1. Water is poured into a neutral bowl (preferably with an enamel coating). About caustic soda is dissolved in it. The volume of a substance depends on the amount of water. It is advisable to obtain a solution of about 5 percent.
2. The workpiece is completely immersed in the resulting solution.
3. The solution with the immersed part is heated to 150 degrees. This is practically a boiling process. It lasts approximately two hours. Using the tool, the quality of the process is checked. If necessary, the time can be increased.

At the final stage, the following operations are performed on the part:

1. The part is removed from the reagent bath.
2. Place it on a flat surface and allow it to cool naturally (without forced cooling). It is advisable to create conditions that limit contact with ambient air.
3. Visually check the quality of the resulting oxidation. The absence of uncovered areas, the density of the formed film, the final color.

Thus, oxidation can be carried out at home. The main thing is to follow these recommendations.

Source: https://stankiexpert.ru/spravochnik/materialovedenie/oksidirovanie-stali.html

How to anodize metal at home?

For most, the beautiful and incomprehensible word “anodization” has associations with complex physical and chemical technologies, laboratory conditions and other scientific paraphernalia.

Not everyone knows that this practical and uncomplicated process can be carried out using the means at hand: anodizing titanium and other metals can be done for real, even at home.

And if you are interested in steel castings, go to the website osnastka74.ru. However, what is it and why is it necessary for metal?

What is anodized metal surface

The name anodization is a process that occurs during the use of an electrolyte and electric current of different magnitudes and makes it possible to obtain a durable oxide foam on the product, which increases the strength of steel and provides protection against rust. Strength and mechanical characteristics vary depending on the composition of the metal, the density and type of electrolyte, the magnitude of the anodic and cathodic influence, calculated using special equations.

Essentially speaking, the protective coating is not applied, but appears from the iron itself during an electrochemical reaction. The technique used in domestic conditions looks schematically like this:

Scheme of the anodizing process in domestic conditions

1. Electrolyte is poured into a dielectric (non-conducting) container.
2. A power supply is taken that can provide the required continuous current voltage at the output (this can be a battery or several batteries combined into electronic circuits).
3. The “+” clamp is connected to the object being processed, and the object is immersed in a container with the solution.
4. The “–” clamp is attached to a lead or stainless steel plate and is also lowered into the liquid.
5. An alternating current of the required magnitude is connected, according to the electrochemical equation. Because of it, oxygen begins to be released on the surface of the product, which contributes to the formation of a durable film for protection.

Pros of anodized metal

Anodic oxidation (anodizing) of a wide variety of metals, carried out in domestic conditions, is, of course, much inferior to that carried out using equipment used in industry. However, it can still provide the product with a number of advantages:

1. Increase corrosion resistance - due to the fact that the oxide film prevents moisture from reaching the metal base, providing excellent protection. Using a similar process on quickly rusting household items or disks and parts of household appliances can significantly increase their service life.
2. Make metal and steel more reliable: oxidized coatings are more resistant to mechanical and chemical damage.
3. Dishes treated in this way are non-toxic, invulnerable to prolonged heating, and food does not burn on them.
4. After anodizing treatment, metal products acquire dielectric properties (they do not conduct current at all or practically).
5. Possibility of galvanic coating of other metals (chrome, titanium). Made with your own hands, it can significantly increase the strength-mechanical characteristics or increase the decorative qualities (gold plating).

Plus, the process will give you the opportunity to decorate. Color anodic oxidation can be created. A similar result can be obtained by changing the equations of the supplied current and the density of the electrolyte (this is real when anodizing titanium and other hard materials is carried out) or by using paint (more often for aluminum and other soft metals, but this process is also used on hard substrates). Objects painted in this way have a more even and deeper color.

The factory method provides greater coating strength, the ability to carry out deep anodizing with the simultaneous application of cathode electrochemical foam, which provides protection against rust. However, even anodic-cathode treatment carried out at home will help make disks or other parts of moving mechanisms quite strong and wear-resistant.

Any ways

There are two options for carrying out the process of oxidizing steel treatment at home. Each of them has its own advantages and disadvantages .

Warm way

A much less difficult process to carry out with your own hands. It flows successfully at a temperature of 20 degrees when using organic paint, providing an excellent opportunity to create extraordinarily beautiful things. For this purpose, you can use both ready-made paints and pharmacy dyes (brilliant green, iodine, manganese).

Hard anodizing cannot be achieved using this technology; the oxide foam is fragile, provides poor protection against rust, and is easily damaged. However, if you paint the surface after this technique, the adhesion (adhesion) of the coating to the base will be too high, nitro enamels or other paints will stick firmly, will not peel off, and provide a greater degree of protection against rust.

Cold way

This technique, when performed in a domestic environment, requires careful control of temperature, allowing it to fluctuate from –10 to +10°C (comfortable temperature for the purpose of conducting an electrochemical reaction according to the equation – 0°C).

It is at this temperature regime that the anodic and cathodic surface treatment proceeds very fully, slowly creating a durable protective oxide film.

This allows the home craftsman to carry out hard anodizing with his own hands, providing the steel with the greatest protection against rust.

Using this technique, you can create electroplating by applying copper, chromium or gold to the product, calculating the current strength using special equations. After such finishing it is very difficult to damage the steel part or discs. Rust protection effectively lasts for a long time even when in contact with sea water, and can be used to increase the service life of underwater equipment.

A small disadvantage is that the paint does not stick to this surface. To give the metal color, the sputtering method (copper, gold) or electrochemical color change under the influence of electric current is used (the current strength and electrolyte density are calculated using a specialized equation).

Anodic oxidation technique

The general process, carried out with your own hands, can be divided into stages:

1. The surfaces of discs and other metal parts are perfectly cleaned of dirt, washed, and sanded.
2. Degreasing is carried out with white spirit or acetone.
3. The required time is maintained in the alkaline solution (it is calculated by the equation based on the structure of the material).
4. Then the disks or other metal products are immersed in an electrolyte, where the anodic and cathodic reaction of growing an oxide film is carried out.
5. If the product has been cold processed, then after removing it from the container it is necessary to wash it very thoroughly from the acid and dry it. After completing this process, it is guaranteed long-term good protection against rust.
6. During the thermal process, the film will be porous, soft, requiring additional fixation, carried out by dipping into clean boiling water or through the influence of hot steam. Afterwards it must be washed well.

Types of electrolytes

At home, not only industrial chemical acid solutions are used, but also affordable products that can be found in every kitchen:

1. When anodizing titanium, you can take sodium chloride, sulfuric or phosphoric acid.
2. For aluminum, oxalic, chromic or sulfuric acids are used.
3. Instead of acids, table salt and baking soda can be used for anodic and cathodic treatment of disks or other steel objects. You can make the desired electrolyte by mixing 9 parts of a concentrated soda solution with one part of saline.

The exposure time of disks, plates, and other objects made of metal in an electrolyte container under current is calculated according to the equation, based on physical and chemical parameters.

Dangerous moments

When using acids as electrolytes, you must strictly follow safety regulations. Ignoring them can lead to accidents:

1. In case of contact with the skin, due to the fact that a diluted drug is used, minor burns are possible. However, this concentration is dangerous for the eyes, so do not neglect protective glasses and gloves.
2. Under the influence of current, oxygen and hydrogen vapors are released, which, when stirred, form an explosive gas. When working in a poorly ventilated area, you can get an explosion from any spark, which can lead to death.

By following safety precautions and innovative processing steps, you can get reliable, beautiful things: chrome rims for a car, create gold-like jewelry, add strength to parts of household mechanisms, depending on the technologies used.

How to easily remove rust from metal at home

Source: http://versace-promo.ru/kraski-klei-gruntovki/kak-anodirovat-metall-v-domashnih-uslovijah/

Anodizing metal at home - Machine tools, welding, metalworking

An attractive appearance and increased strength properties of a metal surface can be achieved by using special electrochemical reactions. One of these methods is anodizing the metal, during which a protective oxide film is formed on the surface, giving the material additional qualities.

Features of anodized

This procedure is widely used on an industrial scale; in addition, you can independently oxidize steel, aluminum or copper at home. The latter option will differ from the professional process, but it is convenient for processing small parts.

Products that have a film formed on their surface after anodizing have the following characteristics:

• increased resistance to corrosion;
• the strength of materials such as steel and aluminum increases;
• the product becomes non-toxic;
• lack of ability to conduct current;
• the prepared surface is suitable for further processing using galvanic coating.

The procedure of anodizing metal is used for the production of cookware - products processed by this method do not burn on the stove and are safe for cooking. Materials with an oxide film are used in the manufacture of some tools, building materials, lighting devices, and household items. In addition, silver products are processed.

Color anodizing is widespread, which allows you to give parts a variety of decor. Products painted in this way have a more even and deeper color.

The anodized surfaces of tools and devices do not crack during use, maintaining their original appearance for a long time. In addition, the plane becomes stronger, which allows it to withstand increased loads and mechanical stress.

How does the anodizing process work?

The whole procedure consists of three stages of work: preparing the metal, its chemical treatment and fixing the coating to the surface. We propose to take a closer look at each of these phases using the example of processing a material such as aluminum:

1. Preparatory stage. The metal profile is cleaned mechanically, after which it is polished and degreased. This must be done so that the coating is firmly fixed to the base. Next comes the use of alkalis. The part is placed in the solution for some time for etching, after which it is transferred to an acidic liquid, where the aluminum is brightened. The final stage of anodic preparation is the complete washing of parts from residual alkali and acid.
2. Chemical reaction. The prepared product is placed in an electrolyte. It is a solution of acid to which a current is connected. The material to be anodized is most often treated with sulfuric acid, and its oxalic analogue is used to achieve color. A successful result is achieved with the correct temperature and current density. Hard anodizing involves the use of low temperatures, but if the goal is to obtain a soft and porous film, the performance increases.
3. Stage of fixing the coating. The resulting aluminum parts with the film formed on them have a porous appearance, so they need to be strengthened. Several methods are used for this: dipping the product in hot water, treating with steam or a cold solution.

For further color painting of the product, there is no need to fix the anodizing. Existing paints and varnishes adhere perfectly to the porous surface, forming excellent adhesion to it.

It is worth noting that metals are coated with such anodizing at industrial enterprises. A particularly durable type of coating can be achieved with a hard type of procedure. This material is used in automobile production, aircraft construction and construction.

Method of procedure at home

When starting anodizing yourself at home, you must first prepare all the tools:

• container for placing the product;
• batteries with a capacity of 9 V (several pieces, depending on the desired result);
• aluminium foil;
• cable with good insulation;
• electrolyte solution;
• ticks.

As an experimental experience, you can try processing the bolts. The thickness of the finished coating is approximately 0.05 mm. Products must be prepared in advance. If stainless steel elements were selected, degrease and sand them in advance.

Prepare an electrolytic solution. To do this you will need sulfuric acid and distilled water. You can purchase acid for the electrolyte at auto stores that specialize in battery repair. The proportions of water and acid should be the same, but you should not use an undiluted substance.

It will take longer to achieve a black metal color than a light or bronze result.

First, etch the part in lye to prepare it. After this, place the part in a solution with electrolyte and connect the current. It is important to use a thermometer to monitor the temperature and ensure that the readings do not drop. When the level reaches the lower levels, it is necessary to end the process.

Source: https://stanki-info.com/anodirovanie-metalla-v-domashnih-usloviyah/

Anodizing metal at home - Metalworker's Guide

Many people associate the beautiful and incomprehensible word “anodizing” with complex physical and chemical technologies, laboratory conditions and other scientific paraphernalia. Few people know that this useful and simple process can be carried out using improvised means: it is possible to anodize titanium and other metals even at home. But what is it, and why is it needed for metal?

The name anodization is a process that occurs when using an electrolyte and electric current of various sizes and allows you to obtain a durable oxide foam on the product, which increases the strength of steel and provides protection against corrosion. Strength and mechanical characteristics vary depending on the composition of the metal, the density and type of electrolyte, the magnitude of the anodic and cathodic effects, calculated using special equations.

The protective coating itself is not applied, but is formed from the iron itself during an electrochemical reaction. The technology used at home looks schematically like this:

Scheme of the anodizing process at home

1. Electrolyte is poured into a dielectric (non-conducting) container.
2. A power supply is taken that can provide the required DC voltage at the output (this can be a battery or several batteries connected in electronic circuits).
3. The “+” clamp is connected to the object being processed, and the object is immersed in a container with the solution.
4. The “–” clamp is attached to a lead or stainless steel plate and is also lowered into the liquid.
5. An electric current of the required magnitude is connected, according to the electrochemical equation. Thanks to it, oxygen begins to be released on the surface of the product, promoting the formation of a durable protective film.

Anodic oxidation (anodizing) of various metals, carried out at home, is, of course, much inferior to that carried out using industrial equipment. But, nevertheless, it can provide the product with a number of advantages:

1. Increase resistance to corrosion - due to the fact that the oxide film prevents moisture from penetrating the metal base, providing reliable protection. The use of this process on quickly rusting household items or disks and parts of household appliances can significantly extend their service life.
2. Increase the strength of metal and steel: the oxidized coating is much more resistant to mechanical and chemical damage.
3. Dishes treated in this way are non-toxic, resistant to prolonged heating, and food does not burn on them.
4. After anodizing treatment, metal products acquire dielectric properties (they do not conduct current at all or almost not).
5. Possibility of electroplating of another metal (chrome, titanium). Made with your own hands, it can significantly increase the mechanical strength characteristics or improve the decorative qualities (gold plating).

In addition, the process allows for decoration. You can do color anodic oxidation. This result can be obtained by changing the equations of the applied current and the density of the electrolyte (this is possible when anodizing titanium and other hard materials) or by using paint (more often for aluminum and other soft metals, but this process is also used on hard substrates). Objects painted in this way have a more even and deeper color.

The industrial method provides higher coating strength, the ability to carry out deep anodizing with the simultaneous application of cathodic electrochemical foam, which provides additional protection against corrosion. But even anodic-cathode treatment carried out at home will help make disks or other parts of moving mechanisms more durable and wear-resistant.

Different ways

There are two ways to carry out the process of oxidizing steel at home. Each of them has its own disadvantages and advantages .

Warm method

The easiest process to do it yourself. It runs successfully at room temperature, when using organic paint, and allows you to create amazingly beautiful things. For this purpose, you can use both ready-made paints and pharmacy dyes (green paint, iodine, manganese).

Hard anodizing cannot be achieved using this technology; the oxide foam is weak, provides poor protection against corrosion, and is easily damaged. But, if you paint the surface after this technique, the adhesion (adhesion) of the coating to the base will be very high, nitro enamels or other paints will adhere firmly, will not peel off, and will provide a high degree of protection against corrosion.

Cold method

This technique, when carried out at home, requires careful control of temperature, allowing it to fluctuate from –10 to +10°C (the optimal temperature for carrying out an electrochemical reaction according to the equation is 0°C).

It is at this temperature regime that anodic and cathodic surface treatment occurs most fully, slowly creating a durable protective oxide film.

This allows the home craftsman to carry out hard anodizing with his own hands, providing the steel with maximum protection against corrosion.

Using this method, you can do electroplating by applying copper, chromium or gold to the product, calculating the current strength using special equations. After such treatment, it is very difficult to damage the steel part or discs. Corrosion protection is effective for many years, even in contact with sea water, and can be used to extend the life of diving equipment.

A small disadvantage is that the paint does not adhere to such a surface. To give color to the metal, the sputtering method (copper, gold) or electrochemical color change under the influence of electric current is used (the current strength and density of the electrolyte are calculated using a special equation).

Anodic oxidation technology

The whole process, carried out with your own hands, can be divided into stages:

1. The surfaces of disks and other metal parts are well cleaned of dirt, washed, and polished.
2. Degreasing is carried out with white spirit or acetone.
3. The required time is maintained in the alkaline solution (it is calculated by the equation based on the structure of the material).
4. After this, the disks or other metal products are immersed in an electrolyte, where the anodic and cathodic reaction of growing an oxide film is carried out.
5. If the product was cold processed, then after removing it from the container it should be thoroughly rinsed from acid and dried. After completion of this process, it is provided with long-term reliable protection against corrosion.
6. During the thermal process, the film will be porous, soft, requiring additional strengthening, carried out by dipping in clean boiling water or by exposure to hot steam. Then you need to rinse it well.

Metal anodizing

Anodizing a metal is a procedure for obtaining an oxide film on the surface of products. PKF "Tsvet" provides this service at affordable prices.

Characteristics

Anodizing steel and non-ferrous metals is carried out in order to obtain a coating that will serve as protection during further use of metal products, as well as for decorative purposes. The oxide film gives products excellent wear resistance.

Currently, anodizing services are used in the processing of aluminum, various types of steel, tantalum and titanium. Carrying out such a procedure for iron and copper profiles is undesirable, since there is a possibility of destruction of the protective coating.

Preparation method

Anodizing metal is an easy and quick process. This process takes place in special baths. Before the coating procedure, sanded products are first degreased. This can be done with any organic solvent such as acetone or gasoline. Then oxides are removed from the surface of the products, which may prevent the smooth application of the oxide layer.

The prepared products are sent for processing. Cathodes and anodes are placed in a bath with an electrolyte, which is a solution of sulfuric acid. The material being processed is attached to the latter using a special mount. Opposite charges are at the same distance from each other. A lead sheet is used as a cathode. When electricity is passed through an electrolyte, a chemical reaction occurs, during which an oxide film is formed on the metal.

At the last stage of the metal anodizing procedure, the finished product is washed and sent for inspection.

This type of metalworking is necessary to increase corrosion resistance.

The main indicators of the process are current density and voltage.

When coating non-ferrous metals such as silver and titanium, the oxide film changes color. This depends on the composition of the electrolyte used.

Also, the change in shade of the processed product depends on the temperament regime. At low temperatures, materials of natural colors are obtained. At elevated levels, the oxide layer will be transparent, which allows the product to be painted in any shade.

Application

Metal anodizing is widely used in many industries. This procedure is an important step in the manufacture of products in mechanical engineering, construction and electrical engineering.

PKF "Tsvet" carries out anodizing; you can find out the price for the service from the company manager by phone. You can also leave a request on the website by filling out the form.

Source: https://pkfcvet.ru/product/anodirovanie_metalla/

Anodizing metal at home

Aluminum alloys are considered excellent materials for the production of a wide variety of parts. Aluminum is easy to process, it is lightweight, has a high level of strength and is completely resistant to corrosion.

However, despite a lot of advantages, this metal does not have an attractive appearance. Painting compounds do not adhere well to the surface of aluminum, and if it is not treated with a special coating, dark spots will appear.

The technology of anodic oxidation of aluminum makes it possible to protect the material from oxidation and improve its appearance.

Anodization (anodic oxidation) is a process that results in the formation of an oxide coating on a metal surface, protecting the surface from oxidation that occurs upon contact with air. In this case, the oxidized area is not eliminated , but a coating with greater hardness is created . This technology is similar to bluing.

Why anodize aluminum surfaces

This metal alloy reacts with oxygen under natural conditions, resulting in a protective coating on the surface. The protective layer prevents aluminum from oxidizing.

But these natural oxides are extremely thin and can be easily damaged. Anodizing can solve this problem.

This procedure, in essence, improves the resistance of the metal alloy to adverse external influences, giving the product a more attractive appearance.

After anodizing, aluminum is not afraid of corrosion. The film created on the surface is characterized by the highest wear resistance. In addition, the coating will not peel off over time .

It is worth noting that this is not the application of a protective layer as such, as in the case of coating the surface of steel with zinc or chromium. During anodizing, a film of oxides is formed from the metal alloy itself. It is interesting that anodizing is relevant not only for aluminum, but also for other materials (magnesium, titanium).

Sometimes anodizing is used to improve the decorative properties of a metal alloy and give it a specific shade. Among the colors today, dark and light golden, matte silver, and pearl tones are especially popular.

In industry, anodization is carried out using a twenty percent sulfuric acid solution. But self-anodizing (at home) using acid is extremely dangerous and not very convenient.

There is another option, which involves the use of a composition of sodium chloride and sodium carbonate. This is ordinary salt and soda, which can be found in any home.

Advantages

As for the advantages inherent in this technology, the following should be noted:

• anodized structures acquire excellent protective properties;
• the metal surface is made uniform and matte;
• Anodizing also allows you to get rid of damage to the coating - stripes, chips, scratches;
• the appearance of the surface of the metal alloy is improved;
• The protective layer after processing is quite thick.

Today, there are several technologies for performing this procedure.

Warm type of coating

This method is quite simple. You can even do all the work yourself. The procedure is carried out at room temperature. Through warm anodizing, you can create an attractive finish in a variety of colors using additional organic dyes. If you try , you can achieve several shades on the same element at once.

Remember Soviet guns, characterized by green colors. This is the result of anodizing an aluminum alloy. And as a coloring agent, ordinary brilliant green was used, which can be found in any pharmacy.

The technology has its advantages, but it is not without its disadvantages.

1. Anodized aluminum does not have a truly high level of anti-corrosion protection.
2. Traces of corrosion on its surface can appear when interacting with aggressive metals and in sea water.
3. This treatment also does not provide effective mechanical protection - the metal surface can be scratched even with an ordinary needle. If the technology was not followed, the coating can be wiped off by hand.

Warm anodizing is extremely simple to perform. To begin with, all elements are thoroughly degreased and fixed in a suspension . Anodizing is carried out until a milky tint appears on the surface, then the product is washed with cool water. The product is painted with a hot solution. The painted coating is fixed within one hour.

Features of cold anodizing

The technique is performed at low temperatures. Cold anodizing was developed for a variety of reasons: high strength, hardness and quality, as well as rapid dissolution and sufficient coating thickness. As a rule, home craftsmen prefer this technology.

The layer located on the side of the metal surface increases, and on the outside it almost completely dissolves.

At the same time, the technology requires good cooling of the elements; only in this case can a high-quality result be achieved. The resulting coating will be very wear-resistant and hard.

For example, underwater guns, the surface of which has been cold anodized, will no longer be afraid of sea water.

The only drawback is the inability to use natural dyes. It all depends on the substances included in the material being processed. The color during processing can vary from dark to greenish .

First, the part is degreased and fixed in a special hanging device. The metal alloy is then anodized until a dense layer appears. After this, it is washed with cold or hot water. At the final stage, the layer is strengthened by boiling in clean water.

Solid oxidation

This technology produces a durable and hard anodized coating. It is actively used in industrial enterprises. A characteristic feature of the technique is that several electrolytes are used to perform it. The electric current density gradually increases and, due to a change in structure, a high-strength film appears on the metal surface.

Equipment for anodizing aluminum at home

Now you know what anodizing is. It's time to figure out exactly what equipment is needed for this. So, for work you will need several trays for parts with different sizes.

They must be made of aluminum. Alternatively, you can use polyethylene or plastic. The top and bottom of the plastic bath should be covered with sheets of aluminum foil.

This is necessary to create a cathode-anode installation.

The bathtub must also have high thermal insulation characteristics. Only in this case the electrolyte will not heat up too much, and you will not need to change it regularly.

After preparing the cathode, it is necessary to make an electrolyte, place it inside the bath, put the element there and connect an electric current source to the “plus”. The lead plate must be connected to the minus.

In order for the metal alloy to begin to anodize, a power supply of one and a half amperes and twelve watts will do. As for the time spent, for small elements the procedure will take approximately thirty minutes.

It will take three to four hours to produce a full aluminum profile.

Product color may vary. It all depends on the anodizing technique used at home. Using aniline paints, metal parts can be painted even in black shades.

Source: https://steelfactoryrus.com/anodirovanie-metalla-v-domashnih-usloviyah/

Anodizing aluminum at home

Aluminum is a low-melting, ductile and soft metal, which is why it is often used by craftsmen to make various parts at home. But aluminum has a drawback.

It has a very unpresentable appearance due to the protective film formed on its surface. In other words, aluminum darkens in air, and when used, it gets your hands dirty, because... the film is unstable. To remedy the situation, aluminum is anodized.

We'll talk about how to do this at home in our article.

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Anodizing aluminum: what is it?

As already mentioned at the very beginning, aluminum, when interacting with oxygen in the air, oxidizes. An oxide film forms on its surface, which is very unstable to mechanical damage. To secure this film and protect it from abrasion, the aluminum is anodized.

How does the property of aluminum parts change after anodizing? That's how:

• the top layer of metal is strengthened;
• visual and tactile alignment of small errors in the metal surface (scratches, pinhole damage, etc.) occurs;
• the process of applying coloring matter to an aluminum workpiece is improved;
• the part takes on a more presentable appearance;
• it becomes possible to imitate various metals (silver, platinum, gold and even pearls).

Hard anodizing of aluminum: advantages and disadvantages

Anodizing aluminum at home can be done in two ways: hard (cold) and warm. The latter, due to its complexity, is practically not used at home, but hard anodizing has become widespread among craftsmen.

This process has its advantages and disadvantages. The first include such as obtaining a thick protective layer that has good strength characteristics, as well as the formation of a high-strength anti-corrosion film on the metal surface.

Among the shortcomings, one is noted: the inability to retain a uniform layer of organic-based dye on its surface. The dye applies unevenly and is not durable. However, during the process of hard anodizing, the workpiece itself is painted in natural colors from greenish, through yellowish-brown to deep gray.

What is needed for hard anodizing

Materials and equipment you will need:

Anodizing to color change

The entire process of anodizing at home can be divided into several stages. But first I would like to dwell on the process of industrial cold anodization, which occurs using a solution of sulfuric acid. As a result of this process, active gas evolution occurs, and volatile gases are explosive. That is why it is not recommended to carry out a similar process at home.

Home anodizing technology is safer. Let's talk about its main stages in more detail.

1. Preparing the necessary solutions
   For hard anodizing, two types of solution are prepared in different containers: one is saline, the other is soda, the basis for which is drinking distilled water of medium temperature (40-50 degrees). You will need nine times more soda solution than saline solution, and therefore an appropriate container is selected for it. Salt is added to warm water with constant stirring (to another soda). Saturated solutions are prepared, i.e. salt and soda are added until a precipitate begins to form. After this, the solutions must be filtered several times. Remember that the quality of anodization depends on the quality of the solutions (their transparency and purity). Before the hard anodizing process itself, the solutions are mixed in a ratio of 1 part salt and 9 parts soda.
2. We prepare the workpiece for anodizing.
   Well, everything is simple here. The workpiece must be thoroughly sanded and degreased.
3. We anodize.
   So, let's start anodizing. The parts must be placed in the bath so that they are completely immersed in the solution and do not touch the bottom or walls of the bath. Then an electric current is applied: to the bath “minus”, to the workpiece “plus”. The workpieces remain under the influence of tension in the bath until they change color. Then the current is turned off, the workpieces are removed and thoroughly washed in running water. Afterwards, the part is placed in a manganese solution, where traces of the salt-soda solution are finally removed from the surface of the part. Then we wash it again. Do you see any stains or streaks on the workpiece? So everything went well.
4. We fix the surface layer.
   As a result of anodization, a film was formed with a large number of pores that need to be closed. This is done by simply boiling in distilled water for half an hour.
5. Varnish or paint.
   To do this, place the anodized workpiece in a container with varnish or aniline paint (10%). That's it, the part is ready.

As you can see, the anodizing process at home is simple and accessible to everyone.

angor58

Source: https://nashprorab.com/anodirovanie-alyuminiya-v-domashnikh-usl/

What is anodized steel?

• Characteristics
• Process
• Materials

• Aluminum
• Titanium
• Steel
• Copper
• Anodizing at home

In the modern world there are a large number of methods for processing metals and metal products. They are used both on an industrial scale and at home.

Anodizing Characteristics

Anodizing is a procedure for forming an oxide film on the surface of various metals by anodic oxidation. The growth of the oxide film is carried out in a conducting medium. This film adheres quite well to the metal surface.

The growth of the oxide film can also be carried out using the method of increasing the temperature regime. However, it turns out to be low in strength and does not last for a long time. Thanks to the electrochemical method of forming the oxide film, it is of optimal thickness and adheres well to the surface of the material.

Different types of metals can be anodized. The main requirement is that they must be able to form only one oxide. It must have the maximum level of stability.

If a metal has the ability to form several oxides at once, this can lead to the film simply starting to crack and no protective effect appearing.

It is for this reason that cases of anodizing iron or copper occur only at rare industrial facilities.

In addition, the oxide film on the surface of metals must have a porous structure. This is necessary so that electrolytes penetrate into it better. As a result, it turns out that only a small part of all metals on earth can satisfy these parameters. These include aluminum, tantalum, titanium. In the industrial and domestic spheres, the most common treatment is anodizing aluminum material.

Anodizing process

The technology for anodizing various types of metals is simple. The main thing is to have at hand everything you need to implement it.

It is carried out in several stages:

• Preparation of metals for the formation of an oxide film.

At this stage, preparatory work for anodizing is carried out. They consist of thoroughly cleaning and washing the metal surface. First, all dirt and deposits are removed. Then the material is washed using water or special solutions. After this procedure it must be dried.

At this stage, a solution with an acidic or any other medium is prepared and connected to the positive plus of the current source.

• Coating the surface of metals or their alloys with an oxide film.

At this stage, the metal or product made from it is immersed in the prepared solution.

Anodizing materials

Today, various metal materials are used for anodizing.

Currently, the following types of anodizing are distinguished depending on the materials used, such as:

Aluminum anodizing

This process is most common today. It consists of coating an aluminum material with an oxide film. In the process, aluminum is lowered into an acidic environment, and the positive plus of the current source is passed to it. As a result, a thin oxide film appears on the material.

Titanium anodizing

Everyone knows that titanium belongs to the category of metals that are widely used in industry, but they have a low level of wear resistance. To give it strength and resistance to different environmental conditions, an anodizing procedure is used. In this case, all anodic processing of the metal is carried out in an acidic environment at a temperature of 40 to 50 degrees Celsius.

Anodizing steel

Anodizing steel is a complex process. For this, either an alkaline or acidic medium is used. As a result, an oxide film is formed, which imparts a high level of strength.

Copper anodizing

Copper is a fairly flexible type of metal. Various methods are used to give it strength. One of them is anodizing. By placing the copper material in an acidic environment, a dense oxide film is formed on the surface, which gives the material a large number of useful characteristics.

Table. Compatibility table of metals and alloys

MaterialAluminiumBronzeDuraluminBrassCopperNickelTinTin-lead alloy (POS solder)Unalloyed steel (carbon) / cast ironChromeZinc

Aluminum	Joint	Not compatible	Joint	Not compatible	Not compatible	Not compatible	Not compatible	Not compatible	Joint	Not compatible	Joint
Bronze	Not compatible	Joint	Not compatible	Joint	Joint	Joint	Soldering	Soldering	Not compatible	Joint	Not compatible
Duralumin	Joint	Not compatible	Joint	Not compatible	Not compatible	Not compatible	Not compatible	Not compatible	Joint	Not compatible	Joint
Brass	Not compatible	Joint	Not compatible	Joint	Joint	Joint	Soldering	Soldering	Not compatible	Joint	Not compatible
Copper	Not compatible	Joint	Not compatible	Joint	Joint	Joint	Soldering	Soldering	Not compatible	Joint	Not compatible
Nickel	Not compatible	Joint	Not compatible	Joint	Joint	Joint	Soldering	Soldering	Joint	no data	Joint
Tin	Not compatible	Soldering	Not compatible	Soldering	Soldering	II	Joint	Joint	Joint	no data	Joint
Tin-lead alloy(POS solder)	Not compatible	Soldering	Not compatible	Soldering	Soldering	Soldering	Joint	Joint	Joint	no data	Joint
Unalloyed steel (carbon)/cast iron	Joint	Not compatible	Joint	Not compatible	Not compatible	Joint	Joint	Joint	Joint	Joint	Joint
Chromium	Not compatible	Joint	Not compatible	Joint	Joint	no data	no data	no data	Joint	Joint	Joint
Zinc	Joint	Not compatible	Joint	Not compatible	Not compatible	Joint	Joint	Joint	Joint	Joint	Joint

Anodizing at home

In the modern world, a large number of metal objects are used in the household sphere, which are used for various purposes. Each owner wants to protect them from corrosion so that they last a long period of time. Anodizing at home is suitable for this purpose.

Important: The procedure for home anodizing of any metal must be carried out outdoors or on the balcony.

First you need to prepare a solution. To do this, you need to mix distilled water and acid in a certain proportion. It is important to handle sulfuric acid with extreme care, because if it comes into contact with the eyes or skin, it can lead to an unpleasant situation.

After this, you can prepare metal parts for processing. All kinds of substances are used for this purpose. They are able to clean them for the procedure.

At the last stage of home anodizing, metal parts are immersed in a solution and an electric current is connected.

anodizing at home

Source: https://varimtutru.com/anodirovannaya-stal-chto-eto/