Duplex Steel Round Bar

Round Bar

M-Pipe & Fitting Solution Inc is a reputable company that manufactures and supplies high-quality duplex steel round bar. Duplex Stainless Steel Round Bar is a type of stainless steel that combines the benefits of austenitic and ferritic stainless steel. It possesses excellent corrosion resistance, high strength, and good weldability. Duplex steel round bars are one of the most commonly used forms of duplex steel. Duplex steel round bars properties, applications, and specifications, explicitly focusing on ASTM A276 Duplex S32205 round bars, Duplex Steel 2205 hex bars  and UNS S31803.

Properties of Duplex Steel Round Bars:

Corrosion Resistance: Duplex steel round bars offer superior corrosion resistance compared to conventional stainless steel. This is due to the high chromium (Cr) and molybdenum (Mo) content, which provides resistance against various corrosive environments such as chloride-containing solutions, acids, and caustic solutions.

High Strength: Duplex steel round bars exhibit high strength, making them suitable for applications that require structural integrity and load-bearing capabilities. The duplex structure, consisting of approximately equal amounts of ferrite and austenite, contributes to the enhanced strength of these round bars.

Good Weldability: Duplex steel round bars are known for their excellent weldability. They can be readily welded using various methods, such as gas tungsten arc welding (GTAW), gas metal arc welding (GMAW), and shielded metal arc welding (SMAW). Proper welding procedures and filler metals specific to duplex stainless steels should be employed to maintain the desired properties of the round bars after welding.

Excellent Toughness: Duplex steel round bars possess excellent toughness, which allows them to withstand harsh operating conditions, including cryogenic temperatures. This property makes them suitable for applications in chemical processing, oil and gas, and marine environments.

Fatigue Resistance: The unique microstructure of duplex steel round bars provides them with excellent fatigue resistance. They can withstand cyclic loading and repetitive stress, making them ideal for applications where durability is essential.

Applications of Duplex Steel Round Bars:

Due to their exceptional properties, duplex steel round bars find applications in various industries. Some typical applications include:

Chemical and Petrochemical Industry: Duplex steel round bars are widely used in chemical processing plants and refineries where they come into contact with corrosive media such as acids, alkalis, and saltwater. Their corrosion resistance and high strength make them suitable for components such as pumps, valves, heat exchangers, and storage tanks.

Oil and Gas Industry: Duplex steel round bars are extensively utilized in offshore and onshore oil and gas exploration and production. They are employed in components such as pipelines, subsea equipment, offshore platforms, and downhole equipment. The superior corrosion resistance of duplex steel ensures the integrity and longevity of these critical components in aggressive environments.

Desalination Plants: Duplex steel round bars are commonly used in desalination plants, where seawater is converted into freshwater. The high chloride resistance and excellent duplex steel pitting and crevice corrosion resistance make it an ideal choice for these plants’ components, such as pumps, valves, and heat exchangers.

Structural Applications: Due to their high strength and good weldability, duplex steel round bars are utilized in structural applications such as bridges, buildings, and industrial equipment. Their ability to withstand heavy loads and harsh environments makes them suitable for these demanding applications.

Specifications of Duplex Steel Round Bars:

The two commonly used specifications for duplex steel round bars are ASTM A276 Duplex S32205 and Duplex Steel 2205 hex bars.

ASTM A276 Duplex S32205 Round Bars: This specification covers hot-finished or cold-finished duplex stainless steel round bars for general applications. ASTM A276 Duplex S32205 is a widely accepted standard for duplex stainless steel round bars and provides specific requirements for chemical composition, mechanical properties, heat treatment, and dimensions.

Chemical Composition: The chemical composition of ASTM A276 Duplex S32205 round bars typically includes elements such as chromium (Cr), nickel (Ni), molybdenum (Mo), and nitrogen (N). The composition may vary within specified limits, but typical values are approximately 22% Cr, 5.5% Ni, 3% Mo, and 0.18% N.

Mechanical Properties: ASTM A276 Duplex S32205 round bars exhibit excellent mechanical properties. The minimum tensile strength is usually around 620 MPa(90ksi), with a minimum yield strength of 450 MPa (65 ksi). The elongation at break is typically above 25%, ensuring good formability and ductility.

Heat Treatment: Duplex steel round bars can be supplied in various conditions, such as annealing, solution annealed, or hardened and tempered, depending on the specific requirements of the application. Heat treatment processes may involve heating the round bars to a specific temperature and then cooling them at a controlled rate to achieve the desired properties.

Dimensions: ASTM A276 specifies the dimensions of duplex steel round bars, including diameter, length, and tolerances. Round bars are available in sizes ranging from 6mm to 350mm in diameter, with lengths typically varying from 2 to 6 meters. Tolerances for diameter and length are provided to ensure precision and consistency in the manufacturing process.

Duplex Steel 2205 Hex Bars: In addition to round bars, duplex steel is also available in hexagonal bar form. Duplex Steel 2205 hex bars offer similar properties and applications as round bars but with the added advantage of their unique shape. Hex bars provide a greater surface area for gripping and can be easily tightened or loosened using standard tools. They are commonly used in fasteners, fittings, and machined components.

Duplex steel round bars, such as ASTM A276 Duplex S32205 round bars and Duplex Steel 2205 hex bars, are versatile and highly sought-after materials due to their excellent corrosion resistance, high strength, good weldability, and other exceptional properties. They find extensive use in chemical processing, oil and gas, desalination, and structural applications. By adhering to specific standards and specifications, manufacturers ensure the consistent quality and performance of duplex steel round bars, making them a reliable choice for demanding environments and critical applications. M-Pipe & Fitting Solution Inc provides certified round bar that meet international standards such as API, ASTM, and ISO 9001:2015.

Specifications:ASTM A276, ASME SA276
Size:6 mm to 120 mm.
Diameter:6mm to 350mm Diameter
Thickness:100 to 6000 mm Length
Finish:Black, Bright Polished, Rough Turned, NO.4 Finish, Matt Finish, BA Finish
Length:1 to 6 Meters, Custom Cut Lengths
Form:Round, Square, Hex (A/F), Rectangle, Billet, Ingot, Forging Etc.


Duplex S318030.030 max2.00 max1.00 max0.030 max0.020 max22.0 – 23.03.0 – 3.54.50 – 6.500.14 – 0.2063.72 min
Duplex S322050.030 max2.00 max1.00 max0.030 max0.020 max21.0 – 23.02.5 – 3.54.50 – 6.500.8 – 0.2063.54 min
 S327500.030 max1.20 max0.80 max0.035 max0.020 max24.00 – 26.003.00 – 5.006.00 – 8.000.24 – 0.3258.095 min
 S327600.05 max1.00 max1.00 max0.030 max0.010 max24.00 – 26.003.00 – 4.006.00 – 8.000.20 – 0.3057.61 min

These elements are carefully balanced to create a material that has high strength, excellent corrosion resistance, and good weldability. Duplex steel round bars are commonly used in industries such as chemical processing, oil and gas, and marine engineering, where their properties make them suitable for use in harsh environments.