309S stainless steel is a high-alloy austenitic stainless steel specifically designed for extreme temperature applications. The low carbon content (denoted by the 'S' suffix) provides enhanced resistance to sensitization and subsequent intergranular corrosion, making it an ideal choice for prolonged exposure to elevated temperatures. Our 309S Stainless steel plates offer exceptional durability, strength, and resistance to oxidation, carburization, and sulfidation.

Key Features & Benefits:

• Excellent Oxidation Resistance: Outstanding resistance to scaling and spalling at temperatures up to 1150°C (2100°F), significantly higher than standard 304/316 grades.

• Low Carbon Content (309S): The carbon content is controlled to a maximum of 0.08%, minimizing the precipitation of chromium carbides during welding and heating in the critical temperature range. This prevents intergranular corrosion and maintains corrosion integrity.

• High Temperature Strength: Retains a high degree of mechanical strength and resistance to creep under load at elevated temperatures.

• Good Corrosion Resistance: Offers superior corrosion resistance compared to 304/316 in a wider range of environments, particularly against sulfides and other aggressive compounds found in high-temperature industrial atmospheres.

• Ease of Fabrication: Exhibits excellent formability and weldability using all standard fusion methods, both with and without filler metals.

Typical Chemical Composition (Weight %):

Mechanical Properties (Room Temperature):

Note: Properties can vary based on plate thickness and heat treatment.

Common Applications:
309S plate is the material of choice for demanding high-heat environments, including:

• Furnace Components: Radiant tubes, combustion chambers, muffles, retorts, and annealing covers.

• Heat Exchangers & Boilers: For parts exposed to extremely high temperatures and corrosive gases.

• Welding Consumables: Used as filler metal or electrode for welding dissimilar metals or for overlaying on carbon steel.

• Chemical Processing Equipment: Components in petrochemical and fertilizer industries requiring heat and corrosion resistance.

• Food Processing: Equipment like oven liners and parts in commercial baking and food processing.

• Aircraft & Automotive: Exhaust systems, heat shields, and turbocharger components.

Available Specifications & Finishes:

• Standards: ASTM A240, ASME SA-240

• Thickness: Available in a wide range to meet your design requirements.

• Width & Length: Custom cut to your specifications.

• Surface Finish: Standard 2B, No. 1, No. 4, BA, or as required.

Why Choose Our 309S Plates?
We provide premium-quality 309S stainless steel plates that undergo rigorous quality control to ensure they meet the highest international standards. Our products are traceable and come with full Mill Test Certifications (MTC/EN 10204 3.1). We offer competitive pricing and reliable global logistics to get you the material you need, when you need it.

Contact Us Today:
For a quotation, technical data sheet, or to discuss your specific application requirements, please contact our sales team. Let us provide you with the high-performance material solution that ensures the longevity and reliability of your high-temperature equipment.