ASTM A790 S32205 Duplex Stainless Steel Pipe for Corrosive Environments
ASTM A790 S32205 duplex stainless steel pipe is a high-strength, corrosion-resistant material well-suited for corrosive environments due to its duplex microstructure and chemical composition of chromium, molybdenum, and nitrogen. It exhibits excellent resistance to chloride stress corrosion cracking, pitting, and crevice corrosion, making it an excellent alternative to austenitic stainless steel in applications such as oil and gas, chemical processing, and offshore engineering. Key properties include a minimum yield strength of 65 ksi, a minimum tensile strength of 95 ksi, and good mechanical properties, including high fatigue strength.
What is the chemical composition of ASTM A790 UNS S32750?
ASTM A790 UNS S32750 (Duplex 2507) is a super duplex stainless steel containing 25% chromium, 4% molybdenum, and 7% nickel. It is used for seamless and welded ferritic/austenitic stainless steel pipe.
S32205 Duplex Stainless Steel Pipe Chemical Composition %
| C | Mn | P | S | Si | Ni | Cr | Mo | N | Cu |
| 0.03 | 2 | 0.03 | 0.02 | 1 | 4.5-6.5 | 22-23 | 3-3.5 | 0.14-0.2 | / |
S32205 Duplex Stainless Steel Pipe Mechanical Property and Heat Treatment
| Tensile Strength Min | Yield Strength Min | Elongation Min | Hardness Max | Temperature °F [°C] | Quench |
| 95ksi,655MPa | 65ksi,450MPa | 25% | 290HBW,30HRC | 1870-2010 [1020-1100] | Air or Water |
Corrosion Resistance
Chloride Stress Corrosion Cracking (SCC): S32205 is extremely resistant to chloride-containing environments, a common failure mode of standard austenitic steels such as 316L.
Pitting and Crevice Corrosion: Its high chromium, molybdenum, and nitrogen contents provide excellent resistance to these localized corrosion conditions.
Acidic and Salty Environments: It performs well in a wide range of corrosive media, including acidic and chloride-rich environments such as saltwater.
Mechanical Properties
High Strength: Its high yield strength and tensile strength contribute to its durability.
Fatigue Strength: The material exhibits good fatigue strength, making it suitable for cyclic loading applications.
Elongation: Significant elongation exceeding 25% indicates good formability.
Composition
Key Elements: This steel's composition consists of high chromium (22-23%), molybdenum (3.00-3.50%), and nitrogen (0.14-0.20%).
Microstructure: This steel has a duplex (ferrite-austenite) microstructure, with a ratio of approximately 50/50 between austenite and ferrite phases.
Quality and Testing
ASTM A790 Standard: Pipe is manufactured in accordance with ASTM A790 specifications.
Testing: S32205 pipe undergoes various tests before shipment, including hydrostatic, tensile, hardness, and nondestructive testing, to ensure quality.
Gnee Steel specializes in the production of various nickel-based alloys. Gnee Steel's product packaging includes steel strapping: Pipes with an outer diameter of 3 inches or less are typically strapped together with polypropylene film to prevent rust during sea transportation, and then secured with steel strapping. Wooden boxes/crates: Pipes are typically packaged in wooden boxes or crates to protect them during transportation, especially those that are longer or have larger diameters. Seaworthy export packaging: Suppliers typically use standard seaworthy export packaging methods, which may include a variety of materials and techniques to protect the pipes during transportation. Tarpaulin packaging: This prevents rain, seawater, and other external factors from penetrating the export wooden crates during transportation. Gnee Steel specializes in the production and sale of alloy materials. Gnee Steel's products are widely used in aerospace, chemical, power, automotive, and nuclear energy industries, and we can provide customized alloy material solutions based on customer needs. For alloy material pricing inquiries or customized alloy material solutions, please contact us for a quote at ss@gneesteel.com.
