Alloy Geek 2205 Duplex Stainless Steel Standard
Alloy 2205, also known as UNS S32205 or EN 1.4462, is a duplex stainless steel alloy that offers a unique combination of both austenitic and ferritic microstructures. This combination of phases provides Alloy 2205 with enhanced mechanical and corrosion properties, making it suitable for a wide range of applications, especially those that require high strength and excellent resistance to corrosion.
The chemical composition of 2205 stainless steel:
- Carbon (C): 0.03% max
- Manganese (Mn): 2% max
- Silicon (Si): 1% max
- Phosphorous (P): 0.03% max
- Sulfur (S): 0.02% max
- Chromium (Cr): 22-23%
- Molybdenum (Mo): 3-3.5%
- Nickel (Ni): 4.5-6.5%
- Nitrogen (N): 0.14-0.20%
- Iron (Fe): Remainder
Key features and characteristics of Alloy 2205:
Duplex Microstructure: The duplex microstructure of Alloy 2205 consists of approximately equal proportions of austenite and ferrite. This combination imparts the alloy with higher strength and improved resistance to stress corrosion cracking compared to standard austenitic stainless steels.
Corrosion Resistance: Alloy 2205 exhibits excellent corrosion resistance, particularly in chloride-containing environments. It is suitable for applications where corrosive agents such as seawater or brine are present.
Strength: The duplex microstructure provides Alloy 2205 with higher mechanical strength compared to traditional austenitic stainless steels. This makes it suitable for structural applications that demand both strength and corrosion resistance.
Weldability: Despite its duplex structure, Alloy 2205 is weldable using common welding methods. However, proper welding procedures are necessary to maintain the balance of phases and corrosion resistance.
Applications: Alloy 2205 is used in various industries, including chemical processing, oil and gas, marine, and pulp and paper. It's used for applications like pipelines, heat exchangers, tanks, and structural components.
Crevice and Pitting Resistance: The alloy's combination of chromium, molybdenum, and nitrogen provides enhanced resistance to crevice corrosion and pitting.
High-Temperature Performance: Alloy 2205 retains its mechanical properties at elevated temperatures, making it useful in applications involving heat and thermal cycling.
Forms: Alloy 2205 is available in various forms, including sheets, plates, bars, and pipes.
Alloy 2205's duplex structure offers a balanced combination of strength, corrosion resistance, and affordability. It's a popular choice for applications where the benefits of both austenitic and ferritic stainless steels are required. Its resistance to chloride-related corrosion issues and its ability to maintain mechanical properties in corrosive and high-temperature environments make it a versatile material for various industries.
XRF standards are thin samples typically around 1/4" thick while OES standards are typically much thicker to allow for sample preparation.
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