309S Stainless Steel Sheet

Stainless steel has become a crucial material in numerous industries due to its corrosion resistance, durability, and aesthetic appeal. Among the many stainless steel grades available, 309S stainless steel sheet stands out as a high-temperature resistant alloy, widely used in demanding environments.

309S stainless steel is a low-carbon version of 309 stainless steel. It belongs to the austenitic stainless steel family, which is known for its excellent weldability and formability. The primary alloying elements in 309S are chromium (22–24%) and nickel (12–15%), which give it exceptional resistance to oxidation and corrosion, particularly at elevated temperatures.

The “S” in 309S indicates low carbon content, which enhances its resistance to sensitization during welding and reduces the risk of intergranular corrosion.

Key Properties

PropertyDescription
Corrosion ResistanceHigh resistance to oxidation and corrosion, especially in high-temperature environments.
Heat ResistanceCan withstand continuous service at temperatures up to 980°C (1800°F) and intermittent service up to 1038°C (1900°F).
WeldabilityExcellent weldability with or without filler metals.
FormabilityGood ductility and ease of fabrication.
StrengthMaintains structural integrity even at high temperatures.

Chemical Composition

ElementContent (%)
Chromium (Cr)22.0 – 24.0
Nickel (Ni)12.0 – 15.0
Carbon (C)≤ 0.08
Manganese (Mn)≤ 2.00
Silicon (Si)≤ 1.00
Phosphorus (P)≤ 0.045
Sulfur (S)≤ 0.030
Iron (Fe)Balance

Applications

Thanks to its excellent heat and corrosion resistance, 309S stainless steel sheet is widely used in:

  • Furnace parts

  • Heat exchangers

  • Boilers

  • Refinery equipment

  • Welding filler materials

  • Annealing covers

  • Kiln linings

  • Chemical processing equipment

Its resistance to high temperatures also makes it ideal for use in thermal cycling applications where materials must endure frequent heating and cooling.

Advantages of Using 309S Stainless Steel Sheet

  • Superior Heat Resistance – Performs well under continuous and intermittent high-temperature exposure.

  • Low Carbon Content – Reduces carbide precipitation and increases resistance to intergranular corrosion.

  • Excellent Mechanical Strength – Maintains strength and toughness at elevated temperatures.

  • Good Fabrication Characteristics – Easily machined, welded, and formed.

  • Extended Service Life – Offers durability even in aggressive industrial environments.


Comparison with 309 and 310 Stainless Steel

Feature309309S310
Carbon Content~0.20%≤ 0.08%~0.25%
Heat ResistanceHighHighVery High
WeldabilityModerateExcellentGood
Corrosion ResistanceGoodGoodExcellent

309S is often preferred over 309 due to its improved weldability and reduced risk of intergranular corrosion, while offering similar heat resistance properties.

309S stainless steel sheet is a premium material tailored for applications requiring outstanding performance at high temperatures. Its combination of strength, corrosion resistance, and formability makes it a reliable choice in industries like chemical processing, power generation, and metallurgy. If you’re looking for a stainless steel grade that offers superior performance under thermal stress, 309S is a top-tier option.

For more details please feel free to send your requirement to email: info@sino-unicorn.com. We will respond as soon as possible.