Stainless Steel
Stainless Steel 310S (UNS S31008) — Composition, Properties & Supply
Stainless 310S (UNS S31008) is a 25Cr-20Ni high-chromium-nickel austenitic grade with carbon ≤ 0.08%. It has outstanding oxidation resistance and high-temperature strength below 1100 °C, making it the standard for furnace parts, heat-treat fixtures and radiant tubes.
What is the chemical composition of Stainless Steel 310S?
| Element | Symbol | Content (wt%) |
|---|---|---|
| Fe | Fe | Balance |
| Cr | Cr | 24.0–26.0 |
| Ni | Ni | 19.0–22.0 |
| Mn | Mn | ≤ 2.00 |
| Si | Si | ≤ 1.50 |
| C | C | ≤ 0.080 |
| P | P | ≤ 0.045 |
| S | S | ≤ 0.030 |
Values are typical specification limits. Actual heat analysis is reported on the EN 10204 3.1 mill test certificate supplied with each shipment.
What are the mechanical properties of Stainless Steel 310S?
| Property | Value | Note |
|---|---|---|
| Tensile strength | ≥ 515 MPa | Room temperature |
| Yield strength (0.2% offset) | ≥ 205 MPa | Room temperature |
| Elongation | ≥ 40 % | Gauge length 50 mm / 4D |
| Hardness | ≤ 217 HB | Brinell / Rockwell |
What are the physical properties of Stainless Steel 310S?
| Property | Value |
|---|---|
| Density | 7.98 g/cm³ |
| Melting range | 1398–1454 °C |
| Thermal conductivity | 14.2 W/m·K |
| Elastic modulus | 200 GPa |
| Maximum service temperature | 1100 °C (continuous oxidation) |
What are the key characteristics of Stainless Steel 310S?
- 25Cr-20Ni — oxidation resistant up to 1100 °C
- Strong creep and rupture strength at temperature
- Low carbon gives good post-weld intergranular corrosion resistance
- Watch for high-temperature corrosion in sulphidising atmospheres
Where is Stainless Steel 310S used?
- Furnace rolls, radiant tubes and hearth rolls
- Heat-treat fixtures and baskets
- Petrochemical cracking and reformer tubes
- Burner nozzles and high-temperature piping
- Cement and metallurgical high-temperature parts
Which standards and specifications cover Stainless Steel 310S?
What product forms are available?
Frequently asked questions
How do I choose between 310S and 309S?
Both are 25Cr/20–22Ni heat-resistant grades. 310S has slightly higher nickel (~20%) and chromium (~25%) and a higher oxidation limit (~1100 °C) with better cyclic oxidation stability. 309S carries ~22% Ni and is typically used for 900–1000 °C furnace parts and automotive exhaust manifolds. Pick 310S for long-term service above 1000 °C or where higher creep life is required; 309S is fine for sub-950 °C service where weldability and cost matter more.
Need Stainless Steel 310S bar, tube, plate or forgings?
Send the grade, dimensions, standard and quantity. We answer within 10 minutes on working days and quote within 24 hours, with EN 10204 3.1 certification.
Request a Quote Chat on WhatsApp +86-156-1827-9078