Introduction

S31803 duplex stainless steel plate (also known as duplex 2205 stainless steel sheet) is a high strength duplex stainless steel that combines the advantages of austenitic and ferritic structures. As a S31803 corrosion resistant stainless steel, it offers significantly higher mechanical strength and superior resistance to pitting, crevice corrosion, and chloride stress corrosion cracking compared to common 304/316 grades. Manufactured to international standards including ASTM A240 S31803 stainless steel plate (ASTM A240 Type 2205), UNS S31803 stainless steel, EN 1.4462 duplex stainless steel, and JIS SUS329J3L stainless steel, this material delivers excellent pitting resistance (PREN ≥32), crevice corrosion resistance, and chloride stress corrosion cracking resistance in aggressive environments. Whether you are a duplex stainless steel 2205 plate supplier or end user, S31803 provides the ideal balance of strength, weldability, and high corrosion resistance for demanding applications.

Chemical components(%)

Mechanical properties

Physical properties

S31803 Duplex Stainless Steel Available Products and Standard

1. ASTM A240 / ASME SA240 

(Chromium and Chromium‑Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and General Applications)

Grade: S31803 / S32205 (Duplex 2205) – duplex stainless steel S31803 high strength
Type: 

• S31803 duplex steel Plate

• S31803 duplex steel Sheet

• S31803 duplex steel Strip

Size Range:

• Thickness: 0.3 – 150 mm (hot‑rolled or cold‑rolled)

• Width: up to 3500 mm

• Length: up to 12000 mm

Surface: Annealed, Pickled, Bright, No.1, 2B, BA, No.4, Mirror

Testing: Chemical analysis, tensile test (Rm ≥620 MPa, Rp0.2 ≥450 MPa), elongation (≥25%), hardness, pitting resistance test, crevice corrosion test, intergranular corrosion test, dimensional inspection

2. ASTM A789 / A790 

(Seamless and Welded Ferritic/Austenitic Stainless Steel Tube / Pipe)

Grade: UNS S31803 / S32205 – S31803 excellent pitting resistance & chloride stress corrosion cracking resistance

Type: 

• duplex 2205 Seamless

• duplex 2205 Welded Tube

• duplex 2205 Pipe (round, square, rectangular)

Size Range:

• Seamless pipe OD: 6.0 – 610 mm

• Welded pipe OD: up to 1219 mm

• Wall thickness: 0.5 – 60 mm

Surface: Annealed, Pickled, Bright (cold drawn), Polished (for hygienic service)

Testing: Chemical analysis, tensile test, flattening test, flaring test, hydrostatic or NDE test, pitting corrosion test, crevice corrosion test, SSC test (per NACE MR0175), dimensional inspection

3. ASTM A276 / A479 

(Stainless Steel Bars and Shapes / for Pressure Vessels)

Grade: S31803 / 2205 – duplex 2205 stainless steel high corrosion resistance for marine & offshore
Type: 

• S31803 stainless steel Bar (round, square, hex, flat)

• S31803 stainless steel Rod

• S31803 stainless steel Profile (angle, channel)

Size Range:

• Round bar: 8 – 355 mm dia (cold drawn or hot rolled)

• Flat bar: 5 – 150 mm thick × up to 500 mm wide

Surface: Annealed, Pickled, Bright, Ground, Peeled

Testing: Chemical analysis, tensile test, hardness test, ultrasonic test (for large diameters), eddy current test, dimensional inspection, optional corrosion test (CL‑SCC, crevice)

Applications

(1)Oil and gas – S31803 duplex stainless steel for oil and gas pipelines, manifolds, and subsea equipment handles sour service (H₂S/CO₂) with excellent resistance to chloride stress corrosion cracking.

(2)Offshore platform – Duplex 2205 stainless steel for offshore platform topsides, risers, and firewater systems withstands splash zone corrosion and high mechanical loads.

(3)Chemical processing – S31803 stainless steel for chemical processing reactors, heat exchangers, and storage tanks resists organic acids, caustic solutions, and chlorinated media.

(4)Desalination – S31803 stainless steel for desalination plants (high-pressure piping, evaporators, brine heaters) offers superior pitting and crevice corrosion resistance in hot seawater.

(5)Marine environment – Duplex stainless steel 2205 for marine environment includes shipbuilding, propeller shafts, and harbor structures, outperforming 316L in saltwater exposure.

(6)Heat exchanger – S31803 stainless steel for heat exchanger tubes and plates provides high thermal conductivity twice that of austenitic grades, plus resistance to fouling and chloride attack.

MONO Group is one of S31803 Duplex Stainless steel Manufacturer & Supplier & Wholesaler from China, We can supply ASTM / DIN / ISO / GB stndard high quality alloy plate, sheet, round bar, tube, pipes, fittings, flange, pls contact us freely for your RFQ to info@monokj.com