Stainless steel alloy AISI 321, 321 H is known for its good resistance to corrosion, retains strength and other mechanical characteristics at elevated temperatures. So, even in the temperature range of +600…+800 °C, when many alloys of other grades lose their characteristics, this material remains unchanged.
It should, however, be remembered that this steel grade is not highly resistant to oxidizing media, although when titanium additives are added, intergranular corrosion does not occur.
By Russian classification the standard of this alloy is designated as, according to GOST.
Chemical characteristics
The standard content of elements that act as additives is as follows:
- carbon - 0.08%;
- manganese - 2.0%;
- phosphorus - 0.045%;
- sulfur - 0.03%;
- silicon - 1.0%;
- chromium - from 17.0 to 19.0%;
- nickel - from 9.0 to 12.0%;
- titanium - 0.5%.
Mechanical, physical indicators
The typical tensile strength is 580 MPa, the elastic limit is 280 MPa, and the elongation to break is 60%. Brinell hardness level - 163 HB. Fatigue strength - 260 MPa.
With an increase in temperature from +600 to +800 degrees Celsius, the tensile strength decreases, respectively, from 390 to 140 MPa. This indicator remains at a much higher level than that of similar alloys. Intermittent exposure is allowed at temperatures up to +810 °C, continuous - at temperatures up to +900 °C.
Applications
Stainless steel alloy AISI 321, 321H used in various industrial sectors. The heat resistance and heat resistance of this brand made it a priority when choosing a material for the production of welded technical equipment.
In particular, it is from this material that furnace fittings, branch pipes, exhaust manifolds, heat exchange equipment, and welded pipes are produced. Many other structures are made from such steel, which are operated at elevated temperatures and must not lose specifications, mechanical properties.
Stainless steel AISI 321, 321H widely used in many industries. This relevance of steel is due to its excellent anti-corrosion properties, increased heat resistance and heat resistance. The operation of products made of stainless steel of these grades is possible at temperatures of +600 - 800 ° C, while they remain unchanged even after a long time.
The only significant disadvantage of stainless steel AISI 321, 321H is that its operation is not possible in oxidizing environments. And this is despite the fact that the steel is not subject to intergranular corrosion due to the addition of titanium to the alloy.
Russian analogue of stainless steel 321 AISI (321H AISI) according to GOST - 12X18H10T.
Application area
Stainless steel is successfully used in various industries, mainly in the manufacture of various welded equipment, for example: welded pipes, furnace fittings, exhaust manifolds and pipes, retorts, heat exchangers and much more.
Chemical composition(ASTM A240)
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ASTM A240 |
Typical |
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Typical annealed properties
All values shown in these tables are not minimum values, they are just one example of the production of AISI 321, 321H stainless steel products.
Mechanical properties at room temperature
Properties at high temperatures
Tensile Strength at Elevated Temperatures
Minimum values of elastic limit at high temperature(1% deformation for a set time at a given temperature)
Elastic (yield) limit before rupture
- intermittent exposure +810 °C;
- continuous exposure to +900 °C.
Heat treatment of stainless steel
Annealing
Stainless steel should be annealed at a temperature between +1050 and +1150 °C. To achieve the ductility of steel after annealing, it is necessary to cool it as quickly as possible.
Vacation (stress relief)
Annealing of stainless steel should be carried out at a temperature of +450 to +800 °C, while it is necessary to avoid the appearance of intergranular corrosion.
Forging interval
Forging of stainless steel should start at +1150 to +1250 °C and finish at +950 °C. The decrease in temperature must be very gradual, as this will ensure an even distribution of carbon. Remember that stainless steel has a significantly longer warm-up time than carbon steel.
Stainless steel welding
AISI 321, 321H stainless steel has a fairly good weldability, which, however, is somewhat worse than that of AISI 304 steel, since titanium is used to increase its melting strength. When welding this stainless steel, the use of 347 series electrodes is recommended.
Characteristics of steel grade 321 / SS 321
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Standard |
ASTM A182 - Standard Specification for Forged or Rolled Pipe Flanges, Forged Fittings, Alloy and Stainless Steel Valves and Parts for High Temperature Service ASTM A213 - Standard Specification for Seamless Ferritic and Austenitic Steel Boiler, Superheater, and Heat Exchanger Tubes ASTM A240 - Standard Specification for Chromium and Nickel-Chromium, Chromium- and Manganese-Nickel Stainless Steels for Plates, Sheets, Strips for Pressure Vessels and General Purposes ASTM A269 - Standard Specification for Seamless and Welded Austenitic Stainless Steel Tubing for General Service ASTM A403 - Standard Specification for Forged Austenitic Stainless Steel Fittings for Piping ASTM A813 - Standard Specification for Single or Double Welded Austenitic Stainless Steel Welded Pipe |
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Classification |
Stainless steel |
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Application |
Sheet metal, pipes, profiles |
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Other names |
USA (ASTM A167) |
Sheet metal |
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USA (ASTM A182) |
Forged and rolled flanges |
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USA (ASTM A213) |
Seamless pipes |
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USA (ASTM A240) |
Flat products |
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USA (ASTM A269) |
Seamless and welded pipes |
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USA (ASTM A271) |
Seamless distillation pipes |
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USA (ASTM A403) |
Pipe fittings |
A403CR321, A403WP321 |
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USA (ASTM A409) |
Welded pipes |
A409 Grade TP321 |
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USA (ASTM A480) |
Rolled plates, sheets, strips |
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USA (ASTM A774) |
Weld fittings |
A774 S32100, A774 Grade 321, TP321 |
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USA (ASTM A813) |
Welded pipes |
A813 S32100, A813 TP321, A831 Grade TP321 |
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AISI 321 steel is a high-alloy chromium-nickel steel with an austenitic structure, increased heat resistance and heat resistance. The use of steel 321 is permissible at temperatures of 600-800 ° C, while products made of steel 321 remain in their original state for a long time.
It has no obvious magnetic properties, is unstable to oxidation and is not subjected to hardening.
The price of steel 321 is high due to the addition of titanium to the composition, but the cost of using AISI 321 quickly pays off.
Chemical composition in% steel 321
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C |
Mn |
P |
S |
Si |
Cr |
Ni |
Ti |
Fe |
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Rest |
Titanium in the chemical composition makes 321 steel resistant to intergranular corrosion.
Mechanical properties of material 321
Physical Properties
Steel density (weight) 321 - 7.79 g/cm 3 .
Characteristics at elevated temperatures
a deformation in 1% for 10,000 hours.
b deformation of 1% per 100,000 hours.
Closest equivalents (analogues) AISI 321
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Germany |
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European (EN) |
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Japan (JIS) |
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Russia (GOST) |
Scope of application
AISI 321 stainless steel is the most commonly used steel grade. Due to the high carbon content in the composition, AISI 321 steel is recommended for use in industries requiring increased resistance to elevated temperatures (up to 800 about FROM). Steel use:
· in the petrochemical, chemical and textile industries;
· in medicine and pharmaceuticals;
· in the production of welded equipment (pipes, retorts, muffles);
· in automotive and aviation construction;
· in the manufacture of boiler bodies, furnace fittings, gas outlet devices, discharge collectors, expansion joints, electric heating elements;
· in the production of heat exchangers and welding equipment;
· in the organization of structures operating in the open air or in conditions of heating.
Welding
AISI 321 / SS 321 stainless steel is welded with 347-series (Nb-stabilized) electrodes, which have good creep resistance in environments above 400°C. After welding heat treatment is not needed, and the seam should be cleaned of scale and passivated.
Treatment
Annealing: at a temperature of 1050°C-1150°C; cooling - in air.
Vacation: at a temperature of 450-800°C.
Passivation: 20-25% HNO 3 solution at 20°C.
Surface cleaning: solution nitric acid and hydrofluoric/hydrofluoric acid in proportions: 10% HNO 3 + 2% HF at room temperature or 60°C. Sulfuric acid solution in proportions: 10% H 2 SO 4 + 0.5% HNO 3 ) at 60°C.
Hot processing: initial temperature - 1150 - 1250°C; final - 950°C.
Remember: stainless steels require 12 times more time to heat up uniformly than carbon steels.
Analoguesanddenominationsbecome: AFNOR Z 6 CNT 18.10; DIN 1.4641; UNI ICL 472 T, UNI KG, UNI KT, UNI kW, UNI X 6 CrNiTi 18 11; JIS SUS 321; SS 2337; BS 321 S 12, BS 321 S 18, BS 321 S 22, BS 321 S 27, BS 321 S 40, BS 321 S 49, BS 321 S 50, BS 321 S 59, BS 321 S 87, BS CDS-20, BS EN. 58V, BSEN. 58C; AMS 5510 AMS 5557 AMS 5559 AMS 5570 AMS 5576 AMS 5645 AMS 5689 ASME SA182 ASME SA193 ASME SA194 ASME SA213 ASME SA240 ASME SA249 ASME SA312 ASME SA320 ASME SA358 ASME SA376 , ASME SA403, ASME SA409, ASME SA430, ASME SA479, ASTM A167, ASTM A182, ASTM A193, ASTM A194, ASTM A213, ASTM A240, ASTM A249, ASTM A269, ASTM A271, ASTM A276, ASTM A312, ASTM A314, ASTM A320, ASTM A358, ASTM A376, ASTM A403, ASTM A409, ASTM A430, ASTM A473, ASTM A479, ASTM A493, ASTM A511, ASTM A580, FED QQ-S-763, FED QQ-S-766, FED QQ-W -423, MIL SPEC MIL-S-862, SAE 30321, SAE J405 (30321), UNS S32100
Corrosion resistance of stainless steel AISI 321
Heat resistance of stainless steel AISI 321
Physical properties of stainless steel AISI 321
Thermal properties of stainless steel AISI 321
Electrical properties of steel AISI 321
AISI 321 steel has high strength, service life, corrosion and heat resistance. It is easy to weld, but inferior in this parameter to the AISI 304 brand. Due to the presence of titanium, the material is not subject to intergranular corrosion even when welding under adverse conditions. However, it is not recommended for use in sulphurous and highly oxidizing environments. Steel feels great in conditions of extremely high and extremely low temperatures, in complex corrosive and aggressive environments, in conditions of high humidity and thermal loads. The material is distinguished by high strength, high heat resistance (up to + 800C), optimal ductility, excellent resistance to ultra-low temperatures and low cost. In addition, steel AISI 321 not hardened, and has no magnetic properties.
UNIQUE CHARACTERISTICS OF AISI 321
Stainless steel sheet AISI 321 produced by cold and hot rolling (depending on the application). The thickness of hot-rolled steel sheet is 4 - 60 mm, cold-rolled cast - 0.5 - 6 mm. Stainless steel easy and convenient in processing, it is formed and welded in different ways. When factory hardened with the addition of nitrogen, steel AISI 321 acquires increased mechanical strength.
BRIEF CHARACTERISTICS OF AISI 321 STAINLESS STEEL
Therefore, the main technical advantages of stainless steel rolled sheet AISI 321 it could be considered:
High strength;
Excellent weldability;
Deep rotation and drawing;
Ease of machining;
The ability to increase the strength characteristics by adding nitrogen;
Heat resistance
APPLICATION OF AISI 321 STEEL SHEETS
Rental stainless steel sheets become AISI 321 used in the construction, food and petrochemical industries in the manufacture of tanks, containers and reservoirs for the storage and transportation of various substances and liquids, as well as a material for the manufacture of prefabricated and welded structures for general purposes. Steel sheet AISI 321 it is widely used in mechanical engineering, chemical, fuel and pulp and paper industries, as well as in cryogenic production at low temperatures (up to -269C). Electrodes of spark plugs, pipes and branch pipes, muffles and heat exchangers, collectors are made from it.
Our company offers AISI 321 stainless steel in the form of flat and long products. We carry out wholesale and retail deliveries of foreign stainless steel High Quality. The sold products have been certified and meet the requirements international standards. At the request of the customer, processing, packaging, delivery of products in Moscow and in various regions of Russia is carried out.
AISI 321 stainless steel sheet with a matt finish is shipped from our warehouse. Depending on the production method, cold-rolled and hot-rolled sheets are distinguished. Web thickness: 0.5-50 mm. Cutting options: 1000x2000, 1250x2500, 1500x3000 and 1500x6000 mm. The offered stainless steel is produced in sheets or rolls with cut and uncut edges. The flatness of products can be normal, improved, high and extra high. Specifications are regulated by GOST 5582-75 and GOST 7350-77. The assortment is specified in GOST 19903-90 and GOST 19904-90.
AISI 321 sheet is used for the production of welded structures resistant to high temperatures. For example, steam lines, heat exchangers, parts of furnace equipment and exhaust systems, tanks and containers for storing or transporting hot liquids.
Long products AISI 321 in our assortment is a calibrated stainless wheel with a matte surface. Size range: 10-100x4100 mm. Technical conditions are regulated by GOST 5949-75. European standard: DIN EN 10060-2004. The assortment is specified in GOST 7417-75.
Sizes and cost of goods are constantly updated, so please contact our managers to quickly and correctly place your order.
Material characteristics
AISI 321 steel is a heat-resistant austenitic stainless steel. The letter marking indicates the standard used, the numbers indicate the category and features of the steel. Chemical composition in%: Cr (17-19), Ni (9-11), C (0.12), Si (0.8), Mn (2), P (0.035), S (0.02), Cu (0.3) and Ti (0.8). The material does not differ in magnetic properties and is not hardened. The domestic analogue is stainless steel 12X18H10T. The first digits indicate the percentage of carbon, and subsequent letters and numbers correspond to the main alloying elements.
AISI 321 steel has high strength, service life, corrosion and heat resistance. It is easy to weld, but inferior in this parameter to the AISI 304 brand. Due to the presence of titanium, the material is not subject to intergranular corrosion even when welding under adverse conditions. However, it is not recommended for use in sulphurous and highly oxidizing environments.
AISI 321 stainless steel is used in construction, engineering, chemical, food, light, pulp and paper and fuel industry. Useful properties pay off the cost of this brand and allow it to enjoy well-deserved popularity among consumers of rolled metal products.
The main difference between stainless steel and other steel grades is the high chromium content (at least 10.5%). This component makes steel wear-resistant and reliably protects it from corrosion. Due to its excellent performance characteristics, stainless steel has found its application in many fields of activity. Especially it is worth noting the following advantages of stainless steel:
Durability of products made of stainless steel (20-50 years);
Unpretentiousness and the ability to operate in almost any conditions;
Ability to manufacture products of various shapes and purposes;
hygiene;
Possibility of surface treatment, processing and welding;
Excellent compatibility with other materials (brick, concrete, stone, glass, wood, etc.)
Types of stainless steel and their main characteristics
In industry, stainless steel is found in several types: austenitic, ferritic, ferro-austenitic and martensitic. The most common is austenitic stainless steel. Due to its composition, which contains up to 7% nickel, this type of stainless steel is ductile, well weldable, non-magnetic and can withstand a wide range of temperatures. Among austenitic stainless steels special attention deserves stainless steel AISI 321 from the company "MetPromStar", which has a high heat resistance and is not subjected to hardening.
The excellent performance qualities of stainless steel have allowed it to become simply irreplaceable in construction, medicine, chemical, food, oil refining industries, as well as in agriculture and mechanical engineering. Stainless steel can be used for the manufacture of various types of metal: strips, corners, hexagons, I-beams, square, circle, etc., which are widely used for the construction of metal structures of various types and purposes. Also, stainless steel AISI321 is quite often used for the manufacture of tanks for various purposes. When working with products from this steel grade, it is allowed temperature regime 400-800 gr.S. It is worth knowing that this brand of stainless steel cannot be used in an intensely oxidizing environment.
Ferritic stainless steel has much in common with mild steels, but at the same time has better corrosion resistance. Ferro-austenitic stainless steel has a structure containing both austenitic and ferritic crystal lattices. This feature makes steel very strong and flexible, which allows it to be used in the petrochemical and pulp and paper industries, as well as in ship repair and shipbuilding. Martensitic steel has a high chromium content (11-13%), which gives it strength, rigidity, and high resistance to corrosion.
Features of the use of stainless steel
The scope of AISI 321 stainless steel is very diverse. One of the clearest examples is the use of stainless steel for the manufacture of tanks for various purposes. Stainless steel tanks are simply irreplaceable in the food, medical, chemical, oil refining industries, as well as in other areas of activity where high hygiene requirements storage, processing, transportation and production of various products.
Depending on the type of rolled metal, stainless steel AISI 321 is actively used in mechanical engineering and automotive industry, construction, medicine, healthcare, electric power, oil production, chemical, Food Industry, in interior design, art and in many other fields of activity. For example, AISI 321 stainless steel hexagons are needed for the manufacture of high-strength fasteners that are used in technical equipment and mechanical engineering. Corners, beams, hexagons are widely used in construction and agriculture. Stainless steel pipes are indispensable in the manufacture of a variety of equipment for manufacturing enterprises.
Stainless steel AISI 321 is increasingly used for decorative interiors, facades of buildings and for the construction of complex metal structures. Modern designers actively use it for finishing and decorating restaurants, discos, offices and other public places. When choosing stainless steel products, it is worth remembering that the correct selection of stainless steel grades for specific operating conditions will ensure a long service life and reliability of products.