Overview
Alloys 309S are austenitic chromium-nickel stainless steels that are often used for higher temperature applications. Due to their high chromium and nickel content, Alloys 309 and 309S are highly corrosion resistant, have outstanding resistance to oxidation, and excellent heat resistance while providing good strength at room and elevated temperatures. The only significant difference between 309 and 309S is the carbon content. Alloy 309S has a much less carbon composition which minimizes carbide precipitation and improves weldability.
309S (UNS S30908) is the low carbon version of the alloy. It is utilized for ease of fabrication. 309H (UNS S30909) is a high carbon modification developed for enhanced creep resistance. It most instances the grain size and carbon content of the plate can meet both the 309S and 309H requirements.
Specification
ASTM A213/A213M-21a Standard Specification for Seamless Ferritic and Austenitic Alloy-Steel Boiler, Superheater, and Heat-Exchanger Tubes.
309S Stainless Steel Pipe & Tubes Specification | ASTM A269, ASTM A213, ASTM A312, ASME SA269, ASME SA213, ASME SA312 |
309S Stainless Steel Pipe & Tubes Grades | 202, 304, 304L, 304H, 304LN, 309S, 310S, 316, 316L, 316H, 316Ti, 316LN, 317L, 321, 321H, 347, 347H, 904L, SMO 254, ALLOY 254, 6MO, 6MOLY, UNS S31254 ETC. |
309S Stainless Steel Pipe & Tubes Type | Seamless / Welded / ERW / EFW / Cold Draw / Hot Finish / Cold Finish |
309S Stainless Steel Pipe & Tubes Outer Diameter Size | Seamless - 1/2"NB TO 18"NB |
309S Stainless Steel Pipe & Tubes Wall Thickness | Schedule 10 to Schedule 160 (3 mm to 100 mm Thickness) |
309S Stainless Steel Pipe & Tubes Length | 01 Meter to 12.5 Meters, Single Random Length, Double Random Length And Customize Size. |
309S Stainless Steel Pipe & Tubes Ends | Plain Ends / Beveled Ends |
309S Stainless Steel Pipe & Tubes Other Testing | Product Analysis, Transverse Tension Test, Flattening Test, Etching Test, Radiograph HIC Examination, Stabilizing Heat Treatment, Intergranular Corrosion Test, Weld Decay Test, Magnetic Particle Detection, Grain Size Test, NACE 0175, Dual Grade, PWHT (POST WELD HEAT TREATMENT), Flare Test, Bend Test, Hardness Test, Tensile Test etc |
Chemical Composition
| Element | 309 | 309S | 309H |
|---|---|---|---|
| Chromium | 22.0 min.-24.0 max. | 22.0 min.-24.0 max. | 22.0 min.-24.0 max. |
| Nickel | 12.0 min.-15.0 max. | 12.0 min.-15.0 max. | 12.0 min.-15.0 max. |
| Carbon | 0.20 | 0.08 | 0.04 min.-0.10 max. |
| Manganese | 2.00 | 2.00 | 2.00 |
| Phosphorus | 0.045 | 0.045 | 0.045 |
| Sulfer | 0.030 | 0.030 | 0.030 |
| Silicon | 0.75 | 0.75 | 0.75 |
| Iron | Balance | Balance | Balance |
Mechanical Properties
| Properties | Metric | Imperial |
|---|---|---|
| Tensile strength, ultimate | 620 MPa | 89900 psi |
| Tensile strength, yield (0.2%) | 310 MPa | 45000 psi |
| Izod impact | 120 - 165 J | 88.5 - 122 ft-lb |
| Modulus of elasticity | 200 GPa | 29000 ksi |
| Shear modulus | 77 GPa | 11200 ksi |
| Poissons ratio | 0.3 | 0.3 |
| Elongation at break (in 50 mm) | 45% | 45% |
| Hardness, Brinell (converted from Rockwell B hardness) | 147 | 147 |
| Hardness, Knoop (converted from Rockwell B hardness) | 164 | 164 |
| Hardness, Rockwell B | 85 | 85 |
| Hardness, Vickers (converted from Rockwell B hardness) | 169 | 169 |
Applications
1. Oven linings
2. Boiler baffles
3. Fire box sheets
4. Furnace components
5. Other high temperature containers.
