• Home
• About
• News
• Contact

If your project lives in a chloride environment and 316L keeps coming back with thin walls or a heavy price tag, it may be time to look at 2205 duplex stainless steel. It is not a niche grade anymore—chemical plants, desalination lines and offshore structures specify it as their default.

2205 is an austenitic-ferritic steel: roughly 22% chromium, 5% nickel, 3% molybdenum and added nitrogen. The mixed structure gives it a minimum yield strength around 450 MPa—about double that of 304 or 316L—so designers can cut wall thickness and weight without losing safety margin.

Corrosion performance is the other half of the story. With a PREN above 32, 2205 resists pitting and crevice corrosion far better than 316L, and its ferrite content makes it notably resistant to chloride stress corrosion cracking—the failure mode that quietly kills austenitic grades in warm seawater or brine service.

There is a cost angle too. With only about half the nickel of 316L, 2205 often prices close to—sometimes below—316L while delivering more strength. That is why storage tanks, heat exchanger shells, pulp and paper equipment and desalination piping keep moving to it.

Two fabrication notes matter. First, keep hot forming in the 950–1150°C range and solution anneal after hot work; sitting between 600 and 950°C invites brittle intermetallic phases. Second, weld with matching 2209 filler and control heat input—standard austenitic practice is not enough.

We supply 2205 (S31803/S32205) duplex stainless steel plates with EN 10204 3.1/3.2 certificates, cut to size for chemical, offshore and desalination projects.