309S Stainless Steel
Stainless Steel 309S is a high-chromium, high-nickel austenitic stainless steel designed for superior oxidation resistance and high-temperature performance. As a low-carbon variant of the 309 grade, it offers enhanced resistance to intergranular corrosion, making it particularly suitable for applications involving prolonged exposure to elevated temperatures and cyclic thermal conditions.
Products Description
Stainless Steel 309S is a high-chromium, high-nickel austenitic stainless steel designed for superior oxidation resistance and high-temperature performance. As a low-carbon variant of the 309 grade, it offers enhanced resistance to intergranular corrosion, making it particularly suitable for applications involving prolonged exposure to elevated temperatures and cyclic thermal conditions.
Corrosion resistance is a standout attribute of 309S. Its high chromium content provides excellent resistance to oxidation in air, making it capable of withstanding continuous service at temperatures up to 980°C (1800°F) and intermittent exposure up to 1095°C (2000°F) without significant scaling. It offers good resistance to sulfur-containing environments and many industrial atmospheres, though its resistance to chloride-induced pitting is comparable to 304 rather than molybdenum-enhanced grades. The low carbon content ensures that its corrosion resistance is retained after welding, eliminating the need for post-weld annealing in most applications.
Chemical Composition
|
C |
Si |
Mn |
P |
S |
Cr |
Ni |
|
|
Min |
- |
- |
- |
- |
- |
22 |
12 |
|
Max |
0.08 |
1 |
2 |
0.045 |
0.03 |
24 |
15 |
Material Properties
|
Density |
Melting Point |
Minimum Mechanical Properties at Room Temperature |
||
|
Tensile Strength |
Yield Strength |
Elongation |
||
|
g/cm3 |
℃ |
Rm N/mm2 |
Rp0.2 N/mm2 |
A5% |
|
7.98 |
1400~1450 |
515 |
205 |
40% |
Feature
The high chromium content enables the formation of a stable chromium oxide protective layer at elevated temperatures, allowing for continuous operation up to 1150°C (intermittent service up to 1035°C). Compared to the 304 series, it offers superior high-temperature oxidation resistance and carburization resistance, though with limited chloride corrosion resistance. The low-carbon composition (≤0.03%) reduces the risk of weld sensitization, making it suitable for applications requiring post-weld reliability.
Applications
Industrial Furnace Components: Heat treatment furnace liners, radiant tubes, burner parts (withstands up to 1100°C)
Petrochemical Equipment: High-temperature cracking furnace tubes, calcination devices
Power Industry: Boiler supports, hot air ducts
Refractory Supports: Glass kiln accessories, ceramic sintering tools
Hot Tags: 309s stainless steel, China 309s stainless steel manufacturers, suppliers, factory, 304H Stainless Steel, stainless steel, 347 Stainless Steel, 317 Stainless Steel, S32205 Stainless Steel, 310S Stainless Steel
Send Inquiry
