309S
Data verified309S is the low-carbon version of 309, preferred for welded high-temperature fabrications because it resists carbide precipitation in weld zones. Oxidation resistance matches 309.
Chemical composition
| Element | Content (%) |
|---|---|
| C | ≤0.08 |
| Si | ≤1.00 |
| Mn | ≤2.00 |
| P | ≤0.045 |
| S | ≤0.030 |
| Cr | 22.00–24.00 |
| Ni | 12.00–15.00 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Delivery condition | Annealed |
| Hardness | ≤217 HB (annealed) |
| Tensile strength | 515–690 MPa |
| Density | 7.90 g/cm³ |
| Max scaling temperature | ~980 °C continuous |
Heat treatment
Solution anneal 1040–1120 °C, rapid cool.
Equivalent grades
| Standard | Designation |
|---|---|
| din | 1.4833 |
| aisi | 309S |
| jis | SUS309S |
| gb | 06Cr23Ni13 |
Compare side by side: 309S vs 309 · 309S vs 310S
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Welded furnace equipment, kiln parts, heat exchangers for hot gas, annealing covers, thermocouple sheaths.
Processing: Good weldability for a high-alloy grade; forming and machining similar to 310S but slightly easier.
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Ask for a quotationVisit NasteelSource: ASTM A240 / EN 10088 published ranges · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.