ASTM A790 Uns s31803 / ASTM A789 Uns S31803 duplex pipe tube is a stainless steel tube with good chloride stress resistance, Uns s31803 contains 21% Chrome 4.5% nickel and 2.5% molybdenum. ‌ASTM A790 S31803‌ Is Duplex stainless steel (austenitic-ferritic) with 22% Cr, 5% Ni, 3% Mo, and 0.15% N, offering high strength/pitting resistance for welded/seamless tubing. ASTM A789 UNS S... https://www.duplexstainlesssteelpipes.com/product/astm-a790-a789-uns-s31803-duplex-pipe-tube/