309S Stainless Steel

Alloys 309 and 309S are austenitic chromium-nickel stainless steels that are often used for higher temperature applications. Due to their high chromium and nickel content, Alloys 309 and 309S are highly corrosion resistant, have outstanding resistance to oxidation, and excellent heat resistance while providing good strength at room and elevated temperatures. The only significant difference between 309 and 309S is the carbon content. Alloy 309S has a much less carbon composition which minimizes carbide precipitation and improves weldability. Specifications: UNS S30900/S30908

Applications:

Alloys 309 and 309S are used exclusively for their high temperature oxidation resistance, excellent high temperature strength, along with their resistance to creep deformation and environmental attack. Some examples include, but are not limited to:

Heating elements

Aircraft and jet engine parts
Heat exchangers
Carburizing annealing products
Sulfite liquor handling equipment
Kiln liners
Boiler baffles
Refinery and chemical processing equipment
Auto exhaust parts

Standards:

ASTM/ASME: UNS S30900/S30908
EURONORM: FeMi35Cr20Cu4Mo2
DIN: 2.4660