Duplex Stainless Steel Round Bars
Duplex stainless steel round bars and rods are a popular choice in the manufacturing industry due to their unique properties. These bars consist of a mixture of austenitic and ferritic stainless steels, which makes them highly resistant to corrosion and oxidation. In this post, we will discuss the various types of duplex stainless steel round bars available in the market and their applications.
Duplex round bars and rods are available in different shapes and sizes, including duplex steel bar, duplex steel bright bar, duplex steel hex bar, round bar duplex ss, duplex spring steel bar, duplex square bar, and duplex flat bar. Each type of round bar has its own set of properties that make it suitable for specific applications.
One of the most popular types of duplex stainless steel round bars and rods is duplex stainless steel s32750. This type of round bar is highly resistant to corrosion and is commonly used in marine environments where saltwater exposure is common. Super duplex steel forged round bars are also used in the oil and gas industry due to their high strength and resistance to corrosion.
Another popular type of duplex stainless steel round bars is Duplex 2205 hex bar. This type of round bar is commonly used in chemical processing plants due to its excellent resistance to corrosion from chemicals such as sulfuric acid.
Types of Duplex Stainless Steel Round Bars
Duplex stainless steel round bars are widely used in various industries due to their excellent corrosion resistance, high strength, and durability. However, not all duplex stainless steel round bars are the same. There are different types of duplex stainless steel round bars that have unique properties and characteristics.
Standard Duplex Stainless Steel Round Bars
The standard duplex stainless steel round bars are made up of equal parts of austenitic and ferritic phases. They have a balanced microstructure that provides them with good mechanical properties such as high strength and toughness. The most common grades of standard duplex stainless steel round bars include ASTM A276 Type 2205 and ASTM A276 Type 2304.
ASTM A276 Type 2205 is a widely used grade for its excellent corrosion resistance and high strength. It contains chromium, molybdenum, and nitrogen which provide it with superior resistance to pitting and crevice corrosion in chloride environments.
ASTM A276 Type 2304 is a low-alloyed grade that has good corrosion resistance in mild environments such as fresh water or atmospheric conditions. It is also known for its cost-effectiveness compared to other grades.
Super Duplex Stainless Steel Round Bars
Super duplex stainless steel round bars have higher levels of chromium, molybdenum, and nitrogen than standard duplex stainless steel round bars. This results in improved corrosion resistance in harsher environments such as seawater or acidic solutions. Super duplex stainless steel round bars also have higher strength than standard duplex grades.
ASTM A276 Type 2507 is a popular super duplex grade due to its excellent corrosion resistance in aggressive environments such as seawater or chemical processing plants. It also has high strength which makes it suitable for heavy-duty applications.
Hyper Duplex Stainless Steel Round Bars
Hyper duplex stainless steel round bars are the newest addition to the duplex family. They have higher levels of chromium, molybdenum, and nitrogen than super duplex grades which provide them with superior corrosion resistance in highly acidic and corrosive environments.
ASTM A276 Type 2707 is a hyper duplex grade that has excellent resistance to pitting, crevice corrosion, and stress corrosion cracking in harsh environments such as seawater or chemical processing plants. It also has high strength which makes it suitable for demanding applications.
Strength and Corrosion Resistance of Duplex Stainless Steel Round Bars
Corrosion resistance is one of the most important properties of duplex stainless steel round bars. Duplex stainless steels offer a combination of high strength and excellent corrosion resistance, making them ideal for use in harsh environments. Compared to austenitic stainless steels, duplex stainless steels have higher tensile strength and better resistance to chloride stress corrosion cracking and pitting corrosion.
ASTM A276 and ASTM A479 are two commonly used specifications for duplex stainless steel round bars. These specifications cover standard requirements for hot-finished or cold-finished rounds, squares, hexagons, and other shapes of wrought duplex stainless steels. The most common alloy grade is S31803, which has a chemical composition that includes chromium, molybdenum, nickel, and nitrogen.
Strength Properties
Corrosion Resistance Properties
Chloride Stress Corrosion Cracking
Pitting Corrosion
Round Bar Length
ASTM A276 and ASTM A479 Duplex Rods
Duplex Stainless Steel Round Bars and Rods Specification
| Specifications | ASTM A276, A479 / ASME SA276, SA479 |
|---|---|
| Grade | Duplex 2205 – UNS S32205/uns S31803 |
| Technique | Cold Drawn, Hot Rolled, Forged Round Bar, Rod, Cold Rolled |
| Tolerance | H8, H9, H10, H11, H12, H13K9, K10, K11, K12 or as per clients’ requirements |
| Standard | AISI, API, ASTM, EN, ASME, BS Round Bars |
| Finish | Cold (bright) drawn, centreless ground, hot rolled, smooth turned, peeled, slit rolled edge, hot rolled annealed, Rough Turned, Bright, Polish, Grinding, Centreless Ground & Black |
| Section | 3.0 to 12.0mm thickness |
| Form | Precision Ground Bar, Flat Bar, Square, Round, Half Round Bar, Rod, Rectangle, Hex (A/F), T-Bar, Channel Bar,Blocks, Round Rod, Threaded, Profiles, Billet, Ingot, I/H Bar, Forging, Rings, Hollow, Triangle etc. |
| Surface | Cold Drawn, Bright, Sand Blasting Finished, Hot Rolled Pickled, Hairline, Polished |
| Processing | Bar cutting to 650mm |
| Certificates | EN 10204 / 3.1 |
| Round bar size | Diameter: 3-~800mm |
| Flat bar size | Thickness: 2 -100mm |
| Width: 10 to 500mm | |
| Hex Bar size | 2-100mm A/F |
| Square bar size | 4 to 100mm |
| Angle bar size | 3mm*20mm*20mm~12mm*100mm*100mm |
| Billet Size | 1/2″ to 495mm Diameter |
| Channel Bar | 80 x 40mm to 150 x 75mm section; 5.0 to 6.0mm thickness |
| Hollow Bar | 32mm OD x 16mm ID to 250mm OD x 200mm ID) |
| Rectangles Size | 33 x 30mm to 295 x 1066mm |
| Condition | Hardened & tempered, annealed |
Duplex Stainless Steel Round Bars and Rods Material Equivalent Grades
| STANDARD | WERKSTOFF NR. | UNS |
|---|---|---|
| Duplex 2205 | 1.4462 | S31803 / S32205 |
Duplex Stainless Steel Round Bars and Rods Surface Finish
| Plate Surface finish | Gauge (in) | Width (max in) |
|---|---|---|
| 2B – Cold rolled, heat treated, pickled, skin passed Plate | 10–24 | 72* |
| 2D – Cold rolled, heat treated, pickled plate | 12–24 | 60 |
| BA Mexinox only | 18–28 | 48 |
| Polished plate (not brushed) | 11–24 | 60 |
| Temper rolled plate Mexinox only | 13–29 | 48 |
Duplex Stainless Steel Round Bars and Rods Chemical Composition
| CD | Cold drawn | P | Polished |
| BD | Bright drawn | SRE | Slit rolled edge |
| CG | Centreless ground | HF | Hot finished |
| CF | Cold finished | HRAP | Hot rolled annealed and pickled |
| P&T | Peeled and turned | RT | Rough turned/peeled |
| ST | Smooth turned | PR | Peeled and reeled |
Duplex Round Bars and Rods Weight
| Size | Kgs / Foot | Kgs / Mtr | Size | Kgs / Foot | Kgs / Mtr | Size | Kgs / Foot | Kgs / Mtr |
|---|---|---|---|---|---|---|---|---|
| 3mm | 0.017 | 0.055 | 20mm | 0.753 | 2.47 | 3″ | 10.9 | 35.762 |
| 1/8″ | 0.019 | 0.062 | 22mm | 0.908 | 2.979 | 3-1/4″ | 12.8 | 41.996 |
| 5/32″ | 0.029 | 0.095 | 7/8″ | 0.926 | 3.038 | 3-1/2″ | 14.85 | 48.772 |
| 4mm | 0.03 | 0.098 | 24mm | 1.08 | 3.543 | 3-3/4″ | 17.001 | 55.78 |
| 3/16″ | 0.043 | 0.141 | 25mm | 1.18 | 3.871 | 4″ | 19.306 | 63.34 |
| 5mm | 0.047 | 0.154 | 1″ | 1.21 | 3.97 | 4-1/4″ | 21.908 | 72.249 |
| 7/32″ | 0.058 | 0.19 | 26mm | 1.271 | 4.17 | 4-1/2″ | 24.4487 | 80.34 |
| 6mm | 0.068 | 0.223 | 27mm | 1.368 | 4.49 | 4-3/4″ | 27.366 | 90.249 |
| 1/4″ | 0.076 | 0.249 | 1-1/8″ | 1.534 | 5.033 | 5″ | 30.461 | 99.94 |
| 7mm | 0.091 | 0.298 | 30mm | 1.691 | 5.548 | 5-1/2″ | 36.69 | 121 |
| 5/16″ | 0.118 | 0.387 | 1-1/4″ | 1.924 | 6.349 | 6″ | 43.86 | 143.9 |
| 8mm | 0.12 | 0.398 | 32mm | 1.894 | 6.314 | 6-1/2″ | 51.093 | 167.63 |
| 9mm | 0.152 | 0.498 | 1-3/8″ | 2.303 | 7.55 | 7″ | 59.432 | 196 |
| 3/8″ | 0.17 | 0.557 | 35mm | 2.39 | 7.553 | 7-1/2″ | 68.226 | 225 |
| 10mm | 0.189 | 0.62 | 36mm | 2.438 | 7.999 | 8″ | 77.586 | 254.55 |
| 11mm | 0.228 | 0.748 | 38mm | 2.792 | 8.903 | 10″ | 121.048 | 397.14 |
| 7/16″ | 0.232 | 0.761 | 1-1/2″ | 2.715 | 8.951 | - | - | - |
| 12mm | 0.271 | 0.889 | 40mm | 3.009 | 9.872 | - | - | - |
| 1/2″ | 0.303 | 0.994 | 1-5/8″ | 3.2 | 10.449 | - | - | - |
| 13mm | 0.318 | 1.043 | 1-3/4″ | 3.712 | 12.179 | - | - | - |
| 14mm | 0.368 | 1.207 | 45mm | 3.807 | 12.555 | - | - | - |
| 9/16″ | 0.383 | 1.256 | 1-7/8″ | 4.26 | 13.977 | - | - | - |
| 15mm | 0.424 | 1.391 | 48mm | 4.33 | 14.205 | - | - | - |
| 5/8″ | 0.473 | 1.551 | 50mm | 4.698 | 15.414 | - | - | - |
| 16mm | 0.481 | 1.578 | 2″ | 4.848 | 15.906 | - | - | - |
| 17mm | 0.543 | 1.791 | 2-1/8″ | 5.475 | 17.963 | - | - | - |
| 11/16″ | 0.573 | 1.88 | 2-1/4″ | 6.135 | 20.128 | - | - | - |
| 18mm | 0.61 | 2.001 | 60mm | 6.768 | 22.205 | - | - | - |
| 3/4″ | 0.682 | 2.237 | 2-3/8″ | 6.838 | 22.435 | - | - | - |
| - | - | - | 2-1/2″ | 7.576 | 24.856 | - | - | - |
| - | - | - | 2-5/8″ | 8.354 | 27.409 | - | - | - |
| - | - | - | 2-3/4″ | 9.169 | 30.083 | - | - | - |
Duplex Stainless Steel Round Bars and Rods Chemical Composition
| Grade | UNS No | C % | Cr % | Ni % | P % | Si % | S % | Mo % | N % | Mn % |
|---|---|---|---|---|---|---|---|---|---|---|
| 31803 | S31803 | < 0.03 | 21.0-23.0 | 4.5-6.5 | 1.03 max | 1 max | 0.02 max | 2.5-3.5 | 0.08-0.2 | < 2.0 |
| 2205 | S32205 | < 0.03 | 22.0-23.0 | 4.5-6.5 | 0.03 max | 1 max | 0.02 max | 3.0-3.5 | 0.14-0.20 | < 2.0 |
Duplex Stainless Steel Round Bars and Rods Mechanical Properties
| Grade | YS (MPa) | UTS (MPa) | % Elongation | Hardness(BHN) |
|---|---|---|---|---|
| 31803 | 450 min. | 620 min. | 25 min. | 293 max. |
| 2205 | 450 min. | 655 min. | 25 min. | 293 max. |
Duplex Stainless Steel Bars and Rods Physical Properties
| Density (Kg / M3) | Modulus of Elasticity (GPa) | Poisson’s Ratio | Thermal Conductivity (W/moC) | Thermal Capacity (I/KgoC) | Electrical Resistivity |
|---|---|---|---|---|---|
| 7800 | 200 | 0.3 | 15 | 500 | 0.8 |
