321 Stainless Steel: Titanium-Stabilized for High Heat

 

What defines 321's chemical composition?​

It contains 17-19% chromium, 9-12% nickel, 0.10-0.20% titanium, and 0.08% max carbon. The titanium binds with carbon, preventing chromium carbide formation in high-temperature environments, which is key for corrosion resistance.​

 

How does 321 perform in high-temperature settings?​

321 retains strength well up to 800℃, resisting oxidation and scaling in continuous heat. It's more stable than 304 in cyclic high-temperature environments, making it ideal for exhaust systems and heat exchangers.​

 

It offers excellent resistance to intergranular corrosion after welding, outperforming 304 in welded structures. It handles mild chemicals and atmospheric conditions well, though it's less resistant to chlorides than 316.​

 

How does 321 compare to 304 in applications?​

321 is preferred for high-temperature welded parts like aircraft exhaust systems, where 304 might corrode. 304 suits general-purpose, lower-temperature applications where cost is a factor.​

 

Where is 321 commonly used?​

Found in aircraft exhaust systems, heat exchanger tubes, and chemical reactor parts. It's also used in furnace components and welded piping for high-temperature service.