1. Standard Designations

• 309 UNS: S30900

• 309S UNS: S30908

• ASTM: A240/A240M

• EURONORM: 1.4828

• JIS: SUS 309/SUS 309S

• GB/T: 12Cr23Ni13 (309) / 022Cr23Ni13 (309S)

2. Chemical Composition (% by weight)

3. Mechanical Properties (Annealed Condition)

4. High-Temperature Properties

• Maximum Service Temperature: 1150°C (2100°F)

• Oxidation Resistance: Excellent due to high chromium content

• Cyclic Oxidation: Superior resistance to thermal cycling

• Creep Strength: Good mechanical strength retention at high temperatures

5. Physical Properties

6. Available Product Range (Plate)

7. Surface Finishes

• No. 1: Hot-rolled, annealed and pickled

• 2B: Cold-rolled, annealed and pickled, light roll pass

• No. 4: Brushed finish

• No. 8: Mirror polish

8. Typical Applications

• Furnace components and radiant tubes

• Heat treatment fixtures and baskets

• Kiln furniture and components

• Refinery and chemical processing equipment

• Welding consumables for dissimilar metals

• Thermal processing equipment

Technical Notes:

• 309S is preferred for welded applications due to lower carbon content

• Excellent resistance to cyclic oxidation and thermal shock

• Suitable for both oxidizing and reducing atmospheres

• Maintains strength at high temperatures better than 304/310 grades

All specifications comply with international standards and are subject to standard manufacturing tolerances. Material test certificates available upon request.