Alloy Geek 317 Austenitic Stainless Steel Standard

Alloy 317, also known as AISI 317 or UNS S31700, is an austenitic stainless steel alloy with a higher content of molybdenum compared to many other stainless steel grades. This increased molybdenum content provides enhanced resistance to corrosion, particularly in chloride-containing environments. Alloy 317 is often chosen for its improved performance in corrosive and high-temperature applications.

The composition of Alloy 317 typically includes:

• Chromium (about 18-20%)
• Nickel (about 11-15%)
• Molybdenum (about 3-4%)
• Carbon (about 0.08% max)
• Manganese (about 2% max)
• Silicon (about 1% max)
• Phosphorus (about 0.045% max)
• Sulfur (about 0.03% max)
• Iron (balance)

Key features and characteristics of Alloy 317:

1. Corrosion Resistance: The higher molybdenum content in Alloy 317 contributes to its improved resistance to corrosion, especially in chloride-containing environments. This makes it suitable for applications involving exposure to seawater, brine, and acidic solutions.

2. High-Temperature Performance: Alloy 317 maintains its mechanical properties and corrosion resistance at elevated temperatures, making it useful in applications involving heat and thermal cycling.

3. Chloride Stress Corrosion Cracking Resistance: The alloy's composition, including the increased molybdenum content, helps mitigate the risk of chloride stress corrosion cracking, which is common in environments containing chlorides.

4. Weldability: Alloy 317 is easily weldable using common welding methods.

5. Applications: It's used in various industries, including chemical processing, pulp and paper, pharmaceuticals, and power generation. Typical applications include heat exchangers, pipelines, and components for corrosive and high-temperature environments.

6. Forms: Alloy 317 is available in various forms, including sheets, plates, bars, and pipes.

7. Versatility: Alloy 317 can be used in environments that demand both corrosion resistance and high-temperature performance.

Alloy 317's combination of enhanced corrosion resistance, high-temperature performance, and versatility makes it suitable for industries where exposure to corrosive and high-temperature environments is common. Its ability to resist chloride-related corrosion issues, such as stress corrosion cracking, is particularly valuable in applications involving seawater or chlorinated environments.

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