Stainless steel AISI 304, 304L widely used in the production of various types of rolled metal - stainless steel pipes, angles, sheets, tapes, hexagons, circles, etc. are made from it. The increased demand for stainless steel AISI 304, 304L is due to its versatility, excellent mechanical properties and chemical composition, as well as a number of other distinctive features, including:
- excellent weldability;
- good oxidation resistance;
- excellent anti-corrosion properties;
- resistance to sudden temperature changes and other climatic influences;
- affordable price.
AISI 304 stainless steel is used in many areas of human activity, and its excellent temperature resistance and anti-corrosion properties are the main advantages over other steel grades. We list just some areas of application of AISI 304, 304L stainless steel:
- Various industries where steel is used in the production of rolled metal and metal structures.
- Reservoirs and containers, as well as pipes for storing and transporting various types of liquids, including drinking water.
Differentiation of 304 AISI steel
Depending on the scope of application and the need for subsequent processing in the production of AISI 304, 304L, Deco stainless steel, it can be manufactured in accordance with certain properties, for example:
- stainless steel strength, heat resistance;
- quality of weldability and subsequent machining;
- deep and rotary hoods;
- stretch molding, etc.
Chemical composition (ASTM A240)
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304L AISI |
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304 AISI |
Mechanical properties at room temperature
To increase the mechanical properties of stainless steel, in particular its strength, it is necessary:
- increase the nitrogen content in steel;
- use repeated skin-pass rolling, which significantly strengthens the steel.
Stainless steel with a high nitrogen content is in most cases used in the manufacture of shipping containers, large tanks and other metal structures where high design strength is required with minimal wall thickness.
Very often, austenitic steel, characterized by increased strength, is used in the production of welded pipes, forming plates, supporting elements of metal structures, chains, strips, etc.
Properties of AISI 304 stainless steel at high temperatures
All values indicated in this table apply only to stainless steel AISI 304. The strength of steel grades 304L and Deco at high temperatures differs significantly (at temperatures above +425 ° C).
Minimum values of elastic limit at high temperature
- Continuous exposure to +925 °C.
- Intermittent exposure to +850 °C.
Properties of stainless steel 304 AISI, 304L AISI at low temperatures
Corrosion resistance
Acidic environments
The table shows only general values for the resistance of stainless steel to various types of acids. The exact resistance values depend on the specific properties of the steel.
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Temperature, °C |
Concentration, % by weight |
Sulfuric acid |
Nitric acid |
Phosphoric acid |
Formic acid |
Code:
0 = high degree of protection (corrosion rate does not exceed 100 mm/year);
1 = partial protection (corrosion rate ranges from 100m to 1000 mm/year);
2 = non resistant - (corrosion rate exceeds 1000 mm/year).
Atmospheric influences
The table shows corrosion values for AISI 304 stainless steel and compares them with other metals under similar weather conditions over a period of time (in this case, the values are based on weather conditions for 10 years).
Heat treatment of stainless steel
Annealing
Annealing of stainless steel, to ensure good anti-corrosion properties, is carried out at high temperatures - from +1010 °C to +1120 °C, after which the steel is quickly cooled by rapid tempering in water or air. The optimal firing temperature to achieve maximum corrosion resistance is +1070 °C.
Vacation (stress relief)
Stress relief for 304L AISI stainless steel is carried out for one hour at temperatures from +450 to +600 °C. The minimum tempering temperature should not drop to +400 °C.
Hot working (forging interval)
Hot processing of stainless steel should be carried out at temperatures from +1150-1260 °C and end at temperatures in the range from +900 to +925 °C. Annealing stainless steel when performing hot working is mandatory.
When performing hot processing of stainless steel, it is important to remember that heating it uniformly to a given temperature takes much longer than heating carbon steels.
Cold processing of stainless steel
Stainless steel grades 304 AISI and 304L AISI are in great demand in many areas of industry, construction and other areas of human activity due to their increased strength, ductility and elasticity. There are several types of cold working of stainless steel - deep and rotary drawing, forming, stretching and bending.
To form stainless steel, it is possible to use machines and tools that are used to process carbon steel, but it is important to remember that such steel has an increased degree of hardening, so much more force is required.
About stainless steel bending
The bending limits of stainless steel sheets depend on the sheet thickness (S) and bending radius (R):
- S< 3мм, мин. R = 0;
- 3mm< S < 6мм, мин. R = 0,5·S, угол гибки 180°;
- 6mm< S < 12мм, мин. R = 0.5·S, угол гибки 90°.
When bending stainless steel, it is important to remember that the return straightening of such sheets is significantly greater than that of carbon steel sheets. Below you can see the approximate values of reverse straightening when bending sheets to a right angle.
- R = S reverse straightening approx. 2°;
- R = 6·S reverse straightening approx. 4°;
- R = 20·S reverse straightening approx. 15°.
When bending austenitic stainless steel, the minimum bending radius must be equal to the thickness of the sheets multiplied by two or more (R = S x 2). If bending of ferritic stainless steel is expected, the minimum bending values should be:
- S< 6 мм, - мин R = S, 180°;
- 6 < S < 12мм, - мин R = S, 90°.
About stretch molding
When performing stretch forming, the workpiece of the future stainless steel product is subjected to so-called “braking”, which occurs during the entire stretching period. Since when this procedure is performed, the walls of the product become very thin, in order to avoid their ruptures, it is necessary to provide for the properties of increased hardening in advance.
Deep drawing and rotary drawing
Deep drawing implies clean drawing without the use of “braking”, although in practice such technology is not used. There is almost always an element of stretch forming involved in the production of stainless steel products.
To perform deep drawing, it is necessary to use only stainless steel with a minimum degree of hardening (Md 30 (N) indicators should be in the minus).
If deep drawing is carried out on special presses, then rotary drawing is carried out on special turning and pressing machines. This technology is in most cases used in the production of any conical products of symmetrical rotation, for example, in the manufacture of buckets.
Stainless steel welding
One of the key characteristics of stainless steel that makes it so popular is its excellent weldability.
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Welding process |
Thickness without weld |
Including weld |
Protective environment |
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Thickness |
Coating |
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Wire |
Bar |
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ER 308 l(Si) W.Nr 1.4370 |
ER 308 l(Si) W.Nr 1.4370 |
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Argon + 5% Hydrogen |
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Argon + Helium |
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(point) -seam (seam) |
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ER 308 l(Si) W.Nr 1.4370 |
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Argon + 5% Hydrogen |
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Argon + Helium |
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ER 308 l(Si) W.Nr 1.4370 |
Argon + 2% CO 2 |
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Argon + 2% O2 |
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Argon + 3% CO 2 + 1% H 2 |
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Argon + Helium |
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Sometimes Argon, Nitrogen |
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After welding stainless steel, no additional heat treatment is required, but it must be taken into account that at the slightest risk of intergranular corrosion, it is necessary to carry out annealing at a temperature of +1050-1150 °C. After welding work, the seam must be cleaned of scale mechanically and chemically, and subsequently passivated.
Decorative stainless steel Deco
Decorative steel of the Deco brand is textured, ground or mirror stainless steel, which is used for external and internal decoration of buildings, as well as for cladding elevators, escalators, commercial equipment, columns, tanks, etc.
The main types of surfaces of stainless steel decorated sheets are presented in our catalog on the corresponding page of the site.
The use of decorative steel allows you to significantly save on the purchase of other finishing materials and at the same time create an original interior or exterior design for many years.
Features of decorative stainless steel Deco:
- resistance to deformation;
- corrosion resistance;
- the highest strength, which is achieved by spraying with titanium nitrite;
- heat resistance;
- elasticity and ease of welding and cutting.
NERZHSTALKOMPLEKT LLC offers you and all its clients supplies of various types of stainless steel products of any grade, in particular AISI and Deco. Prompt delivery of products to any city in Russia, a large assortment, flexible pricing policy, round-the-clock customer support - we have tried to create a company that guarantees timely delivery of any quantity of high-quality stainless steel products.
At the beginning of the last century, specialists in the metallurgical industry noticed that the interaction of chromium and oxygen is better than with iron. It was at that time that in order for the air to have the least effect on iron, metallurgists began to mix it with chromium. This is how stainless steel appeared, which today is an indispensable material for modern industry.
Important: It should be noted that it is practically impossible to completely rid iron of corrosion. Sooner or later, even stainless steel also becomes covered with rust. True, this requires more time.
Stainless steel is an attractive material for use in modern industry. It consists of iron and chromium impurities.
Attention: In order to ensure the longest possible protection of iron from corrosion, it is necessary to add at least ten percent chromium to it during the production of stainless steel.
Also, other elements are added to the mixture for the production of stainless steel, which are presented:
- nickel,
- niobium,
- molybdenum,
- titanium.
They are necessary for the material to acquire its physical and chemical qualities and become more durable.
Thanks to the mixture of iron and other elements, a material is created that can resist corrosion. Depending on the proportionality of the added elements, the stainless material becomes durable and can withstand even high temperatures. Due to its ductility, stainless steel is used in a wide variety of industries.
Iron itself becomes rusty quite quickly. If you mix it with chromium and other elements, an invisible film is formed on its surface, which prevents the flow of oxygen to it. As a result, no oxidation occurs. This layer is quite durable. Which makes the material more resistant to the formation of cracks, dents and many other defects. Steel can repair itself over time.
Stainless steel grades and their characteristics
In the modern world there are more than two hundred and fifty types of stainless steel. They differ in their series or brands and in their properties. The most popular grades of stainless steel currently are those types that belong to the 300 and 400 series. They have a high level of resistance to corrosion. In addition, their layer of protective film is quite durable due to the optimally selected proportionality of the elements used in production. Stainless steel of these series has high strength and ductility. It is actively used for the production of various items in modern industry. Soon, these series may be competed by the 200 series of steel, which, according to consumers, has the optimal combination of cost and quality.
Characteristics of AISI stainless steels
In the modern market, stainless steel of the three hundredth series is in great demand. It is divided into several types depending on the chemical composition:
- austenitic,
- austenitic-ferritic,
- austenitic-martensitic.
These types of steel contain different amounts of nickel and chromium. carbon. 
AISI 304 stainless steel
aisi 304 (08Х18Н10) is widely used in the food industry. It is excellent for welding and to resist rust. 
AISI 316 stainless steel
aisi 316 (10Х17Н13М2) is formed if an element such as molybdenum is added to aisi 304 (08Х18Н10) steel. This grade of stainless steel is widely used in the shipbuilding, oil and gas and chemical industries. It is resistant to aggressive environments.
AISI 316T stainless steel
aisi 316T (10Х17Н13М2Т) о has a high level of strength due to the fact that it contains more titanium than previous brands. It has found wide application in the creation of equipment for the chemical and food industries.
AISI 321 stainless steel
aisi 321 (12-08Х18Н10Т) with the largest amount of titanium among all brands of the three hundredth series. Able to withstand heating temperatures up to 800 degrees Celsius.
AISI 430 stainless steel
Among the brands of the four hundredth series, the most widely used brand is aisi 430 (12X17). In general, the entire series is characterized by the fact that it includes stainless steel grades that are created with a high chromium content. The aisi 430 brand is characterized by the fact that the material bends well and is subject to welding. This steel can be used for places with high temperature changes. Most often it is used for decoration of buildings and in the oil and gas industry.
Stainless steel AISI 201
The 200 series of stainless steel also has worthy brands that you should pay attention to. Among them, the most prominent steel is AISI 201 (12X15G9ND). It differs from more expensive brands from other series in that it uses a mixture of elements such as nitrogen and manganese instead of nickel. Due to its chemical and physical properties, it is widely used in the food and medical industries. It is also suitable for the production of various types of fences and pipes.
| Stainless steel standards | Content of alloying elements, % | |||||||||
| * | DIN | AISI | GOST | C | Mn | Si | Cr | Ni | Mo | Ti |
| C1 | 1.4021 | |||||||||
| F1 | 1.4016 | |||||||||
| A2 | 1.4301 | |||||||||
| 1.4948 | ||||||||||
| 1.4306 | ||||||||||
| A3 | 1.4541 | |||||||||
| A4 | 1.4401 | |||||||||
| 1.4435 | ||||||||||
| 1.4404 | ||||||||||
| A5 | 1.4571 | |||||||||
| 1.4845 | ||||||||||
Stainless steel standards
There are state standards for different types of stainless steel in our country. They determine the quality of products made from this material. Stainless steel has different GOST standards. Certain quality standards are developed for thin sheets, for wire, for thick sheets and for stainless steel pipes.
Stainless steel has different characteristics. Thanks to its chemical and physical parameters, it easily resists the formation of corrosion plaque. This material was developed for use in places where there are different environmental conditions. Due to its heat resistance and strength, steel does not react with substances in the environment.
Modern industry cannot do without the use of stainless steel. It is not only a high-strength material, but also has an attractive appearance. It was because of its beauty that steel began to be used for the decoration of buildings and their individual elements. In particular, fencing and railings for staircases are made from stainless steel.
In the food industry, rolled steel is very popular. Cooking equipment and utensils are made from steel materials. They are able to withstand high heating temperatures and are not susceptible to rust.
The use of stainless steel in the chemical industry began in the middle of the last century. The most durable types of steel material are used here so that equipment or devices do not fail under the influence of various reagents.
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In the modern world, stainless steel is an indispensable material in the production of different types of products. It is used in the food, medical, metallurgical and military industries.
One of the most popular steel grades is AISI 304. Steel of this grade belongs to the austenitic group. The austenitic group is characterized by high density and ductility, as well as resistance to corrosion and temperature changes. The carbon content in stainless steel of this grade does not exceed 0.08%, while the coefficient of chromium and nickel content ranges between 18-20% and 8-10.5%.
The AISI marking system was developed by the American Iron and Steel Institute and is one of the most common in the world. It is used for labeling products and raw materials imported into the countries of Asia and Eastern Europe, along with national systems. In our country, AISI 304 corresponds to brand 08Х18Н10.
AISI 304 steel type is characterized by the presence of a thin layer of chromium oxide on the surface. This layer reliably protects the product from corrosion even under the influence of aggressive chemicals, food essences, water, soil, sudden temperature changes, etc. Unlike other types of steel, AISI 304 stainless steel can be welded without any restrictions.
AISI 304 is a stainless steel with a low percentage of carbon. Due to the versatility of its physical characteristics, this steel grade is one of the most popular not only in Russia, but also in other countries near and far abroad. AISI 304 steel grade is used to make equipment that is used in catering, food and chemical industries.
In addition, equipment for storing and transporting chemicals, wine, beer, and milk is made from this stainless steel. In addition, cutlery and kitchen utensils, architectural parts and pipes are made from AISI steel. Due to the fact that this steel does not accept hardening, it is not suitable for knife production.
Steel composition:
C 0.08%- carbon content in the alloy is 0.08%. Carbon is the most important element in steel; it increases its strength and gives the metal good hardness.
Сr 18.0 - 20.0%- chromium content in the alloy is 18.0 - 20.0%. Chrome is a greyish-white, shiny hard metal. Chromium affects the ability of steel to harden, gives the alloy anti-corrosion properties and increases its wear resistance. Contained in stainless steel of any grade.
Mn 2.0%- the manganese content in the alloy is 2.0%. Manganese is used at the steelmaking stage. Capable of increasing the hardness of steel. Various durable things are made from steels with a significant manganese content - rails, safes, and so on.
NI 8.0 - 10.5%- nickel content in the alloy - 8.0 - 10.5%. Nickel increases the corrosion resistance of steel and can slightly increase strength.
Si 1.00%- silicon content in the alloy - 1.00%. Silicon increases the strength and wear resistance of steel. Like manganese, it makes steel more stable and reliable.
P 0.045%- phosphorus content in the alloy - 0.045%. Phosphorus is one of the harmful technological impurities in steels and alloys. An increase in its content even by a fraction of a percent, while increasing strength, simultaneously increases fragility. The harmful effects of phosphorus are especially pronounced at high carbon levels. The limits for phosphorus content as a technological impurity are 0.025...0.045%.
S 0.03%- sulfur content in the alloy - 0.03%. Sulfur, like phosphorus, is a harmful technological impurity in steels and alloys. An increase in sulfur content significantly reduces the mechanical and physicochemical properties of steels, in particular, ductility, impact strength, abrasion resistance and corrosion resistance. The limits for sulfur content as a technological impurity are 0.035...0.06%.
1 product with this characteristic was found in the catalog.
Steel grade AISI-304 non-magnetic (austenitic) low-carbon. Contains carbon no more than 0.08%. This type of steel has a high density and, at the same time, remains quite ductile; it is also characterized by the highest levels of corrosion resistance and the ability to withstand various temperature conditions.
Due to the uniformity of the chemical composition, AISI 304 steel retains its internal structure even if the outer layer is damaged. In addition, on the surface of this brand, when interacting with atmospheric oxygen, a protective oxide film is immediately formed, which guarantees resistance to the effects of alkali and acid solutions.
The use of Aisi 304 steel is quite wide. It is used for the manufacture of containers, tanks, receivers, various containers, industrial tanks, for the transportation of wines and their storage, for the manufacture of containers for kvass, for the dairy industry, and in the production of cosmetics.
Аisi 304 is highly polishable, as a result of which it can be used in various design works for the decoration of offices and homes.
AISI 304 pipe is used almost everywhere; it is used in plumbing work, in the manufacture of heated towel rails, radiators, used for the design of railings and fences, as well as in the manufacture of ramps, balconies, office furniture and bar counters.
Aisi 304 steel pipes are used to produce support stands for pipelines, various supporting structures, and metal shelving.
Resistance to temperature and influence of alkaline and acidic environments, meeting GOST 5632-72, relatively cheap cost, make this brand quite popular in various fields.
AISI 304 sheet is used for the manufacture of various containers and reservoirs, in the chemical and food industries, for the manufacture of special metal tables (cutting, kitchen, medical).
AISI 304 sheet is also used to produce: platform trolleys, washing and disinfection chambers, doors for refrigerated cabinets,
Thin sheets of AISI 304 are used for cladding elevator cabins, cladding escalators and columns.
This grade of steel is easy to weld. After welding, this grade of steel does not require heat treatment. After welding, the seams must be chemically or mechanically cleaned of scale and then passivated.
AISI 304L easily finds a large number of applications, as it is extremely durable, ductile and elastic. Common operations include contouring, bending, rotary drawing, drawing, etc. During forming it is possible to use the same tools and machines as for carbon steel grades, but here the required force is 50-100% greater.
The annealing temperature range is 1050°C ± 25°C followed by rapid cooling in water or air. After annealing, etching and passivation are required.
Chemical composition in % of AISI 304 steel
| Brand | WITH | Ni | S | P | Cr | Ti | Si | Mn | Cu |
| 304 | ≤ 0.8 | 9-11 | ≤ 0.02 | ≤ 0.035 | 17-19 | ≤ 0.5 | ≤ 0.8 | ≤ 0.2 | ≤ 0.3 |
Mechanical properties AISI 304 (room temperature)
Mechanical properties AISI 304
Physical properties of AISI 304
| Physical properties | Density | Melting point | Specific heat | Thermal expansion | Average coefficient of thermal expansion | Electrical resistivity | Magnetic permeability | Modulus of elasticity |
| Unit of measurement | - | OS | J/kg.K | W/m.K | 10-6.K-1 | Ωmm2/m | at 0.8 kA/m | MPa x 103 |
| Temperature (оС) | 4 | |
20 | 20 | 20-100 20-200 20-400 | 20 | 20 | 20 |
| Meaning | 7,93 | 1420 | 500 | 15 | 16,0 16,5 17,5 | 0,73 | 1,015 | 200 |
AISI 304 product range
Standard sizes of AISI 304 stainless steel sheet
Standard sizes of stainless steel pipe AISI 304
The American Steel and Alloy Institute (AISI) has its own labeling of manufactured steel products that are used in the US and EU. The digital designation is used for carbon and alloy steels, determining the group of steel and the amount of carbon it contains, multiplied by 100. The letter marking indicates the presence of certain alloying impurities in the steel, and also notes some of its characteristics, for example, that it was smelted in an electric furnace or has a high content of sulfur and phosphorus.
Characteristics of AISI 304
304 steel is a high alloy steel with low carbon content (< 0,08 %), т.е. входит в класс аустенитных сталей, отличающихся антикоррозийной стойкостью, жаропрочностью, устойчивостью к агрессивной среде. Добавление к стали 304 буквы L свидетельствует о наличии всего 0,03 % углерода («H» показывает более высокое его содержание).
Alloying of the grade, which increases its performance properties, is carried out using chromium additives, which makes AISI 304 stainless steel; nickel, which strengthens the crystal structure, increases strength, improves ductility and the possibility of subsequent technological processing. In addition to Cr and Ni, additional impurities improve the quality of steel 304:
- nitrogen – to improve corrosion resistance (sometimes instead of carbon and nickel)
- manganese - a large amount makes steel brittle, but in the right quantities increases its hardness
- titanium – in addition to the same qualities as other additives, it helps to change the crystallite structure and improves subsequent processing
- Niobium – rarely added, but also improves strength and corrosion resistance
- molybdenum – helps create a homogeneous steel structure, increasing its strength
- tungsten – to enhance resistance to high temperatures + hardness
- silicon – improves elasticity and anti-corrosion properties
- vanadium – increases its wear resistance, strength, hardness
An analogue of AISI 304 steel in Russia according to GOST is the 08Х18Н10 grade, and AISI 304 L is 03Х18Н11 – acid-resistant metals that can withstand temperatures up to 900°C (short-term). They have good mechanical characteristics, which expands their use in various sectors of the economy.
AISI 304 is the main grade among stainless steels
The qualitative characteristics allow the use of 304 steel where steel products need to withstand high temperatures and aggressive chemical exposure, including not only chimneys, ventilation systems, but also nuclear reactors and thermal power plants. Anti-corrosion properties are valued when transporting and storing wine, milk, beer, chemicals, in the manufacture of household kitchen utensils, etc.
This brand is used for the needs of architectural decoration, in pipes for various purposes, incl. automobile exhausts. AISI 304 stainless steel is of great importance for the production of surgical equipment and medical needles. Drilling rigs, the paper industry, marine and textile equipment, plumbing fittings, hypodermic needles, mining and processing plants and much more cannot do without it.