309S Brief introduction 309S stainless steel is a highly alloyed austenitic stainless steel used for its excellent oxidation resistance, high-temperature strength, and creep resistance. The lower nickel content of Stainless Steel 309, compared to Stainless Steel 310, improves its resistance to hydrogen sulfide (H2S) attack at high temperatures. It is tough and ductile and can be readily fabricated and machined. SS 309S is the low-carbon version, and is recommended for applications where sensitization and subsequent corrosion by high temperature gases or condensates during shutdown may pose a problem. Chemical composition C Si Mn Cr P S Ni ≤0.08 ≤1.00 ≤2.0 22.0-24.0 ≤0.045 ≤0.03 12.0-15.0 Physical property Tensile Strength Yeild Strength Elongation Reduction of Area Density ≥515MPa ≥205MPa ≥40% ≥50% 7.98g/cm3 Application stainless steel 309s is used for its high-temperature oxidation resistance and resistance to H2S attack for applications such as furnace parts, muffles, retorts, firebox sheets, high-temperature containers, catalytic converters, and exhaust systems, radiant tubes, fluidized bed coal combusters, petroleum refineries and steam boilers, thermowells, carbon saggers, paper mill equipment, power boiler tube hangers, anchor bolts, gladd forming equipment, food processing industry.