Product Introduction: 904L Super Austenitic Steel Tube
Material Summary and Usage
904L super austenitic steel tube is a specialized grade of stainless steel known for its exceptional resistance to corrosion and high performance in aggressive environments. Specifically, 904L is designed to withstand corrosive attack from a variety of acids, making it an ideal choice for industries such as petrochemical, chemical processing, and environmental protection. With its high nickel and molybdenum content, this alloy exhibits superior activation and passivation characteristics, which contribute to its outstanding durability in challenging conditions.
The unique composition of 904L includes elevated levels of chromium, molybdenum, and copper. This formulation allows for a low corrosion rate in the passivation area due to the high chromium content, while the high levels of nickel enhance resistance to stress corrosion cracking. Additionally, the molybdenum and chromium work in tandem to provide excellent resistance to pitting and crevice corrosion, particularly in environments with chlorides. Consequently, 904L is highly effective against non-oxidizing acids such as sulfuric and phosphoric acids, ensuring longevity and reliability across its applications.
Chemical Composition
The chemical composition of 904L as per ASTM and DIN standards is as follows:
| Component |
% Content (Max) |
| Carbon (C) |
0.020 |
| Silicon (Si) |
1.00 |
| Manganese (Mn) |
2.00 |
| Phosphorus (P) |
0.045 |
| Sulfur (S) |
0.035 |
| Chromium (Cr) |
19.0 - 23.0 |
| Nickel (Ni) |
23.0 - 28.0 |
| Molybdenum (Mo) |
4.0 - 5.0 |
| Nitrogen (N) |
≤ 0.15 |
| Copper (Cu) |
1.0 - 2.0 |
Mechanical Properties
The mechanical properties of 904L are noteworthy, providing strength and durability while maintaining a high degree of ductility:
| Property |
Value (Minimum) |
| Tensile Strength (sb) |
≥ 490 MPa |
| Yield Point (ss) |
≥ 220 MPa |
| Elongation Rate (d5) |
≥ 35% |
| Hardness (HB) |
≤ 187 |
| Hardness (HRC) |
≤ 90 |
These properties make 904L suitable for applications requiring strength and flexibility under diverse conditions.
Application Fields
The versatility of 904L super austenitic steel tubes positions it as a crucial material across various sectors:
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Petrochemical Industry: The ability of 904L to resist corrosive substances permits its use in processes involving butyl acetate, methyl acetate, and terephthalic acid. Its performance is especially beneficial in manufacturing equipment and pipelines that handle aggressive chemicals.
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Chemical Processing: Its effectiveness against sulfuric and phosphoric acids makes 904L suitable for various applications within the inorganic chemical industry, including reactors, storage tanks, and heat exchangers.
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Environmental Technology: 904L is utilized in manufacturing calcining furnaces and flue gas scrubbers, contributing to emissions control and environmental sustainability. Moreover, its application in coolers for seawater, semi-salt water, and polluted water further illustrates its role in protecting against environmental damage.
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Marine Applications: Due to its superior resistance to both localized and generalized corrosion, 904L is favored in marine environments where exposure to chlorides is prevalent.
Conclusion
In summary, 904L super austenitic steel tubes are a high-performance solution for industries demanding exceptional corrosion resistance, strength, and durability. With its unique chemical composition and mechanical properties, 904L effectively addresses the challenges posed by corrosive environments, making it an indispensable material in petrochemical, chemical processing, and environmental sectors. Adopting 904L can lead to extended equipment life, reduced maintenance costs, and improved safety, reinforcing its status as a premier choice in advanced materials engineering.
For industries looking to enhance their material performance and achieve compliance with stringent environmental regulations, 904L presents an innovative approach that not only meets but exceeds contemporary expectations in material science.
