904L stainless steel and 316L stainless steel
Gnee Steel
The difference between 904L stainless steel and 316L stainless steel
904L and 316L are both austenitic stainless steels, but 904L offers superior corrosion resistance due to its higher chromium, nickel, and molybdenum content, along with the addition of copper. This makes 904L particularly suitable for applications involving strong acids, seawater, and other harsh environments, while 316L is preferred for its superior corrosion resistance.
Gnee Steel
What's so special about 904L steel?
904L alloy offers excellent resistance to uniform corrosion, pitting corrosion, crevice corrosion, and chloride-induced stress corrosion cracking (SCC). In sulfuric, phosphoric, and fatty acid environments, it outperforms 316L and 317LMN.
Chemical Composition of 904L and 316L : Key Differences
The difference in chemical composition between 904L and 316L significantly affects their performance:
904L: Contains higher levels of nickel (up to 23%) and molybdenum (up to 4.5%), as well as copper, which increases its resistance to acids and chlorides.
316L:Lower nickel (10-14%) and molybdenum (2-3%) contents limit its corrosion resistance compared to 904L, but make it a more economical choice.
|
Element |
AISI 316L Stainless Steel (%) |
AISI 904L Stainless Steel (%) |
|
Fe |
Balance | Balance |
|
Cr |
16.0 – 18.0 | 19.0 – 23.0 |
|
Ni |
10.0 – 14.0 | 23.0 – 28.0 |
|
Mo |
2.0 – 3.0 | 4.0 – 5.0 |
|
Cu |
– | 1.0 – 2.0 |
|
C |
≤0.03 | ≤0.02 |
|
Mn |
≤2.00 | ≤2.00 |
|
Si |
≤1.00 | ≤1.00 |
|
P |
≤0.045 | ≤0.045 |
|
S |
≤0.03 | ≤0.035 |
|
N |
≤0.10 | ≤0.10 |
Corrosion Resistance Comparison
904L stainless steel offers excellent corrosion resistance in a wide range of corrosive environments, making it the preferred choice for applications involving aggressive chemicals and chlorides. Key features include:
904L:Its high nickel and molybdenum content makes it highly resistant to pitting and crevice corrosion, particularly in chloride-rich environments such as seawater and chemical plants.
316L: 316L is also corrosion resistant but is more susceptible to attack by chlorides and is less suitable for extreme environments than 904L.
904L is commonly used in applications such as desalination, chemical processing, and oil and gas extraction, where corrosion resistance is critical.
Mechanical Properties and Temperature Resistance
904L and 316L also have different mechanical properties that affect their suitability for different applications:
904L: Offers higher tensile strength and maintains its mechanical properties at elevated temperatures, making it suitable for high-temperature applications such as nuclear power and oil refining.
316L: Offers good tensile strength but is more suitable for applications requiring general strength and moderate temperature resistance.
904L's excellent mechanical strength under extreme conditions makes it an ideal choice for harsh environments, while 316L is a practical choice for standard industrial uses.
Applications of 904L vs 316L Stainless Steel
904L and 316L are widely used, but their unique properties make them suitable for different applications:
904L Stainless Steel:
Chemical Processing: Excellent resistance to sulfuric acid corrosion makes it an ideal choice for chemical plants.
Marine Environments: Used in desalination and other chloride-rich environments.
Oil & Gas: Suitable for high-sulfur environments due to its excellent resistance to stress corrosion.
316L Stainless Steel:
Food and Beverage Industry: Suitable for sanitary applications requiring moderate corrosion resistance.
Pharmaceutical Equipment: Widely used due to its ease of cleaning and resistance to moderate chemical corrosion.
Marine Construction: Suitable for structural components exposed to seawater, but not for extreme corrosive conditions.
Reference table of differences: 904L and 316L stainless steel
| Property | 904L Stainless Steel | 316L Stainless Steel |
| Nickel Content | High (up to 23%) | Moderate (10-14%) |
| Molybdenum Content | High (up to 4.5%) | Moderate (2-3%) |
| Corrosion Resistance | Superior in aggressive environments | Good for moderate conditions |
| Mechanical Strength | High, retain strength at elevated temperatures | Good, suitable for general purposes |
| Cost | Higher | Lower |
| Applications | Chemical, marine, oil and gas | Food, pharmaceutical, marine construction |
Gnee Steel specializes in the production and sale of a wide range of stainless steel products, including pipes, plates, bars, coils, and fittings in 304, 316, 321, 904, 904L, 2205 Duplex, 2205 Duplex, and 316L stainless steel. Gnee Steel's products are widely used in the kitchen, aerospace, chemical, power, automotive, and nuclear energy sectors. We also provide custom stainless steel solutions tailored to customer needs. For stainless steel pricing or custom alloy solutions, please email ru@gneesteelgroup.com for a quote.
