Stainless steel is divided into grades or families according to the properties and chemical compositions of the alloys.
Austenitic stainless steel is a well-known and most commonly used family of stainless steel due to its outstanding properties.
There are four common groups of stainless steel: austenitic stainless steel, martensitic stainless steel, ferritic stainless steel, and duplex stainless steel.
It is used in many industrial and domestic applications, and its demand is increasing day by day.
Austenitic stainless steel has a high percentage of nickel and chromium, and it is non-magnetic.
Due to the fine combination of elements, it has excellent corrosion resistance and strength.
The hardness of this grade can be increased by cold working because hot working is not suitable for this particular grade of steel. It also has good formability and is easily weldable.
301 Austenitic Stainless Steel
Grade 301 (S30100) stainless steel is a commonly used grade of austenitic stainless steel with a nominal chromium and nickel content of 17% and 7%, respectively. This grade of steel is an ideal choice for decorative structural applications due to its high strengths in the six accessible tempers, resistance to atmospheric corrosion, and brilliant, beautiful surface.
It contains 16-18% chromium, 6-8% nickel, 2% manganese, and 0.15% carbon in its composition. Type 301 has a lower chromium and nickel content, which improves its cold work-hardening range. Automobile molding and trim, wheel covers, conveyor belts, kitchen equipment, roof drainage systems, hose clamps, springs, and truck and trailer bodies are some examples of grade 301 stainless steel applications.
304L Austenitic Stainless Steel
Alloy 304L is a T-300 series austenitic stainless steel with a minimum of 18% chromium and 8% nickel. The maximum carbon content of grade 304L is 0.030%. The grade 304L is known as the low-carbon version of grade 304.
Alloy 304L is the most versatile and commonly used stainless steel alloy. It contains 18-20% chromium, 8-12% nickel, 2% manganese, and 0.03% carbon in its composition. Alloys 304L demonstrates great corrosion resistance and has a higher ease of manufacturing, as well as outstanding formability, making it ideal for a wide range of household and commercial applications.
316L Austenitic Stainless Steel
After 304 stainless steel, the most prevalent austenitic stainless steel is 316L grade stainless steel, also known as marine grade stainless steel.
After iron, the principal alloying ingredients are chromium (16-18%), nickel (10-12%), and molybdenum (2-3%), with trace amounts of silicon, phosphorus, and sulfur (1%).
Concerning localized corrosive attack by chlorides and overall corrosion by reducing acids like sulfuric acid, the inclusion of molybdenum gives stronger corrosion resistance than 304.
317L Austenitic Stainless Steel
Grade 317L (UNS S31703) is a corrosion-resistant austenitic chromium-nickel-molybdenum stainless steel with low carbon content. The alloy is more resistant to corrosive conditions that contain chlorides, sulfurous media, and other halides.
It has 18-20% chromium, 11-15% nickel, 3-4% molybdenum, 2% manganese, and 0.03 carbons in its composition. Due to its low carbon content, grade 317L can be welded with no intergranular corrosion.
316LVM Austenitic Stainless Steel
Stainless Steel 316LVM, often known as ‘Medical Grade,’ is vacuum melted to attain the exceptionally high levels of purity and ‘cleanliness’ required for surgical implants. It is resistant to general and intergranular corrosion, pitting, and crevice corrosion in natural conditions. These properties make it useful for medical applications as well as high-precision electronics.
This type of 316 Stainless Steel has more nickel, less carbon, less molybdenum, and less chromium than ordinary 316L. It contains 17-19% chromium, 13-15% nickel, 2.25-3% molybdenum, 0.03% carbon and 0.05% copper in its composition.
316LMod Austenitic Stainless Steel
The 316Lmod grade was created specifically for urea plant operations.
It is a 316L-modified stainless steel with a significantly lower silicon concentration and significantly greater molybdenum content.
Due to its low carbon content and well-balanced chemistry, the alloy is entirely austenitic, with no intermetallic phase precipitations.
It contains 18% chromium, 13.5% nickel, 2.5% molybdenum, 0.3% carbon, and 0.5% silicon in its composition. The alloy was developed to improve corrosion resistance in urea-carbonate conditions.
316Ti Austenitic Stainless Steel
316Ti (UNS S31635) is a titanium-stabilized version of 316 austenitic stainless steel with molybdenum.
This grade has 16-18% chromium, 10-14% nickel, 2-3% molybdenum, 0.08% carbon, and 0.7% titanium in its composition. The addition of titanium in type 316Ti supports the structure against chromium carbide precipitation.
321 Austenitic Stainless Steel
Grade 321 stainless steel is a stable austenitic stainless steel with the addition of titanium, similar to type 304.
This titanium additive decreases or eliminates carbide precipitation during welding and temperatures ranging from 800 to 1500 degrees Fahrenheit and 427 to 816 degrees Celsius. It also improves the alloy’s high-temperature properties.
309S Austenitic Stainless Steel
Alloy 309 (UNS S30900) belongs to the austenitic stainless steel family designed for high-temperature corrosion resistance.
Under non-cyclic circumstances, the alloy is resistant to oxidation up to 1900°F (1038°C). 309S (UNS S30908) is a grade of the 309 alloy family that is also known as the alloy’s low-carbon variant. It has a max of 0.08% carbon in its composition. It is used to ease of fabrication.
310S Austenitic Stainless Steel
Type 310S is a high-temperature chromium-nickel austenitic stainless steel with strong creep strength that resists oxidation in dry air at temperatures up to 2000°F.
In thermal cycling applications, grade 310S performs better than grade 309 stainless steel. Type 310S is a low-carbon variant of Type 310 that is used for simplicity of fabrication due to its improved formability and weldability.
347H Austenitic Stainless Steel
Type 347H stainless steel is a high-carbon austenitic stainless steel. It is used in applications requiring high-temperature resistance and has the same resistance and corrosion protection as Alloy 304.
When annealing is not practicable, grade 347H is generally utilized for heavy welded equipment. It offers stronger high-temperature creep qualities than 347 due to its increased carbon content.
725LN Austenitic Stainless Steel
725LN stainless steel, commonly known as 310MoLN, is a completely austenitic stainless steel with no intermetallic phases like the intergranular carbide precipitations.
The 725LN (310MoLN) steel grade has a chemical composition that has been optimized for use in urea factories. The nitrogen in the chemical composition aids in the stabilization and reinforcement of the austenitic phase.
S30815 Austenitic Stainless Steel
Grade S30815 stainless steel, offers outstanding service qualities at high temperatures and is easy to fabricate.
It has exceptional oxide stability, high raised temperature (creep) strength, great resistance to sigma phase precipitation, and resists oxidation at temperatures up to 1150°C.
And More Austenitic Stainless Steel
Along with the grades stated above, some other grades of austenitic stainless steel play a major role in the industry, including 201, 202, 205, 303, 330, 384, 348, 316F, etc.
Conclusion
The austenitic stainless steel family is versatile in industrial and domestic applications due to its wide range of grades and exceptional properties.
All the grades are very popular with the variations of chemical compositions.
We are dealing in high quality stainless steel materials and customized products. Contact us for the guidelines about choosing the proper austenitic stainless steel grade for your project.
