309S Austenitic Stainless Steel – High-Chromium Heat-Resistant Workhorse

Description

309S is a high-chromium austenitic stainless steel, specifically engineered for high-temperature applications requiring excellent oxidation resistance. With 22.0-24.0% chromium and 12.0-15.0% nickel, it offers superior oxidation resistance at temperatures up to 900°C, outperforming 304 and 316 series grades in high-heat environments. The "S" designation indicates a low carbon content (≤0.08%), which prevents sensitization and enhances weldability, making it suitable for welded high-temperature components. Unlike standard heat-resistant grades, 309S maintains good ductility and formability, while resisting scaling and oxidation in industrial heating environments. It is non-magnetic at room temperature and widely used in furnace parts, heat exchangers, and other components exposed to sustained high temperatures.

Chemical Composition (wt%)

C ≤ 0.08, Cr: 22.00-24.00, Ni: 12.00-15.00, Mn ≤ 2.00, Si ≤ 1.00, P ≤ 0.045, S ≤ 0.030

Mechanical Properties

Tensile Strength ≥ 515 MPa, Yield Strength ≥ 205 MPa, Elongation ≥ 40%, Hardness ≤ 217 HB

Advantages

Excellent high-temperature oxidation resistance (up to 900°C); low-carbon design for good weldability; non-magnetic; good ductility and formability; resistant to scaling in high-heat environments; cost-effective for heat-resistant applications.

Applications

Furnace linings, heat exchangers, boiler parts, incinerator components, industrial heating elements, and high-temperature ductwork.

Equivalent Grades

AISI 309S, UNS S30908, EN 1.4833, GB 06Cr23Ni13

Stainless Steel Suppliers

If you have project requirements for stainless steel, we welcome your order. GNEE has a large inventory of popular products for you to choose from. It can be processed into various practical product forms, including plates, coils, tubes, bars, wires, etc. For detailed chemical composition information and free samples, please contact our factory immediately. We offer competitive prices and excellent service.Email: info@gneestainless.com

 

Testing and Documentation: Factory test certificate, EN 10204 3.1, chemical report, mechanical report, destructive testing report, non-destructive testing report, PMI test report, visual inspection report, third-party inspection report, NABL certified laboratory report.
Packaging: Wooden crate packaging, bubble wrap packaging, steel strapping, or packaging according to customer requirements.