What is the material type A276 S31803?

ASTM A276 S31803 is a duplex stainless steel product specification widely used for bars, wires, and profiles in demanding industrial environments. Buyers frequently search for "What type of material is A276 S31803?" to confirm whether this grade is suitable for high-strength, corrosion-resistant components required in applications such as oil and gas, chemical processing, marine, and pressure equipment.

 

What is ASTM A276 S31803?

ASTM A276 is a standard specification covering stainless steel bars and shapes, while UNS S31803 represents a duplex stainless steel grade. It is a duplex (ferritic-austenitic) stainless steel, and ASTM A276 S31803 stainless steel bars are supplied in hot-worked or cold-worked bar form, possessing high mechanical strength and excellent corrosion resistance.

Common equivalent grades:
Duplex 2205
EN / W.Nr. 1.4462
ASTM A182 F51 (for forgings)
ASTM A790 S31803 (for pipes)

ASTM A276 S31803 bar  Size & Tolerance Specification 

Product Form	Size Range	Length	Tolerance
Round Bar	Ø6 mm – Ø450 mm	3 m / 6 m / random	Diameter h9 / h11 (cold drawn), ASTM standard (hot finished)
Flat Bar	Thickness 6–100 mm × Width up to 600 mm	3–6 m	Thickness ±0.2 mm, Width ±1 mm
Square Bar	6 × 6 mm – 100 × 100 mm	3–6 m	±0.2 mm
Hex Bar	Across flats 10–80 mm	3–6 m	±0.2 mm

 

 

ASTM A276 S31803 duplex stainless steel Chemical Composition (Typical)

ASTM A276 S31803 duplex stainless steel typically contains:

Chromium (Cr): 21.0–23.0%

Nickel (Ni): 4.5–6.5%

Molybdenum (Mo): 2.5–3.5%

Nitrogen (N): 0.08–0.20%

Carbon (C): ≤0.03%

This alloy balance results in a PREN value of approximately 34–36, significantly higher than 316/316L.

 

ASTM A276 S31803  Mechanical Properties (Typical, Solution Annealed)

Property	Value
Yield Strength (0.2%)	≥450 MPa
Tensile Strength	620–880 MPa
Elongation	≥25%
Hardness	≤290 HB

 

What Is ASTM A790 / A276 / A182 F51 ?

The duplex stainless steel system includes multiple ASTM specifications for different product forms:

ASTM A276 S31803: Bars and shapes for machining and structural components

ASTM A790 UNS S31803: Seamless and welded pipes for corrosive service

ASTM A182 F51: Forgings for flanges, fittings, and valves

 

GNEE Supply Capability (Product-Oriented)

GNEE supplies ASTM A276 S31803 bars, ASTM A790 pipes, and ASTM A182 F51 forgings with:

Stable chemical composition

Controlled heat treatment

Full traceability (EN 10204 3.1 MTC)

Dimensional inspection and optional third-party testing

Our experience in oil & gas, chemical, marine, and pressure equipment projects ensures customers receive technically sound duplex stainless steel materials without generic marketing content.