What is a Super Duplex Steel Round Bar?
Super Duplex Steel Round Bars are the high-performance evolution of standard duplex alloys. By raising chromium to around 25% and balancing nickel, molybdenum and nitrogen, these bars hold a near 50/50 microstructure of ferrite and austenite. That dual-phase structure is what gives a super duplex round bar roughly twice the yield strength of austenitic 304/316 while delivering elite resistance to chloride pitting, crevice attack and stress corrosion cracking.
Every super duplex bar we supply carries a PREN value above 40, which is the industry threshold that separates true super duplex from standard duplex. Combined with high tensile strength, excellent dimensional accuracy, a long service life and low maintenance cost, this makes Super Duplex Steel Bars the default choice for seawater, sour-service and high-chloride process environments where even 904L or SMO 254 would struggle on strength.
Super Duplex Steel Round Bar Manufacturer & Supplier in India
Jade Alloys is a Mumbai-based manufacturer, stockist and exporter of premium Super Duplex Stainless Steel round bars produced to meet and frequently exceed ASTM, ASME and NACE requirements. With modern production facilities, in-house heat-treatment records and a qualified technical team, every super duplex round bar is finished to precise tolerance and verified for ferrite balance before dispatch.
We fulfill orders of any scale, from single-piece custom cuts and small trial batches to large project tonnage for EPC contractors, while keeping pricing competitive against imported mill material. Streamlined logistics from JNPT and Nhava Sheva keep your critical projects on schedule. Ready stock, cut-to-length service, and third-party inspection (Lloyd’s, BV, SGS, TUV, DNV) can be arranged on request — see our Quality and Certificate pages, or download the Catalogue.
Super Duplex Steel Round Bars List
We stock and manufacture the two most vital grades of super duplex steel:
Super Duplex Round Bar Specification
| Feature | Details |
|---|---|
| Specifications | ASTM A276, ASTM A479, ASTM A182, ASTM A484 / ASME SA276, SA479, SA182 |
| Grades | UNS S32750 (F53), UNS S32760 (F55), 1.4410, 1.4501 |
| Standard Sizes | Round: 3 – 800 mm | Square: 4 – 100 mm | Flat: 2 – 100 mm | Hex: 2 – 100 mm A/F |
| Bright Bars | 4 mm – 100 mm OD |
| Forged Bars | Up to 800 mm OD |
| Length | 1 to 6 metres (custom cut lengths available) |
| Operating Temperature | -50 °C to 300 °C |
| Tolerance | H8–H11 & G5–G6 (ISO h6–h11 available) |
| Density | 7.8 g/cm³ |
| Melting Point | 1350 °C |
| Hardness | ≤ 300 HB |
| Surface Finish | 6 RA, 32 RA, 63 RA |
| Finish Types | Black, Bright Polished, Rough Turned, Peeled/Turned, No. 4 Finish, Matt Finish, BA Finish |
| Form | Round, Square, Hex (A/F), Rectangle, Flat, Threaded, Hollow |
| Condition | Annealed, Solution Annealed, Hardened & Tempered, Precipitation Hardened |
| Manufacturing Technique | Hot Rolled, Forged, Cold Drawn, Peeled & Ground |
| HS Code | 72222099 |
Need a quick weight estimate before you order? Use our Metal Weights Calculator.
Chemical Composition of Super Duplex Steel Round Bar
| Grade | C | Mn | P | S | Si | Ni | Cu | N | Cr | Mo |
|---|---|---|---|---|---|---|---|---|---|---|
| Super Duplex (Max.) | 0.030 | 1.20 | 0.025 | 0.010 | 0.80 | 8.00 | 0.50 | 0.32 | 26.0 | 4.50 |
Super Duplex Bar Mechanical Properties
| Grade | Elongation | Tensile Strength Rm | Yield Strength Rp0.2 | Impact, Charpy-V, −46 ºC [J] | Hardness |
|---|---|---|---|---|---|
| Super Duplex | ≥ 25 % | ≥ 750 MPa | ≥ 550 MPa | ≥ 65 | ≤ 300 HB |
| UNS S32750 | ≥ 25 % | ≥ 800 MPa | ≥ 550 MPa | ≥ 65 | ≤ 300 HB |
| UNS S32760 | ≥ 25 % | ≥ 750 MPa | ≥ 550 MPa | ≥ 65 | ≤ 300 HB |
Super duplex delivers greater strength than standard duplex stainless steel, making it ideal for high-stress and high-impact environments and giving superior performance under extreme conditions.
Super Duplex Round Bar Physical Properties
| Density | Modulus of Elasticity | Thermal Expansion | Thermal Conductivity |
|---|---|---|---|
| 7.8 g/cm³ | 200 GPa | 30–100 °C (86–212 °F) | 31.5 /μΩ·in, 80 /μΩ·cm |
Key physical characteristics: high thermal conductivity, low thermal expansion, and a low coefficient of thermal expansion — all of which reduce distortion during welding and thermal cycling.
Types of Super Duplex Forged Bars
Stainless Steel Super Duplex Round Bar Tolerance
| Dia – mm | 1 < 3 | 3 < 6 | 6 < 10 | 10 < 18 | 18 < 30 | 30 < 50 | 50 < 80 | 80 < 120 | 120 < 180 | 180 < 250 | 250 < 275 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| ISO h6 | 0.006 | 0.008 | 0.009 | 0.011 | 0.013 | 0.016 | 0.019 | 0.022 | – | – | – |
| ISO h7 | 0.010 | 0.012 | 0.015 | 0.018 | 0.021 | 0.025 | 0.030 | 0.035 | – | – | – |
| ISO h8 | 0.014 | 0.018 | 0.022 | 0.027 | 0.033 | 0.039 | 0.046 | 0.054 | 0.063 | 0.072 | 0.081 |
| ISO h9 | 0.025 | 0.030 | 0.036 | 0.043 | 0.052 | 0.062 | 0.074 | 0.087 | 0.100 | 0.115 | 0.130 |
| ISO h10 | 0.040 | 0.048 | 0.058 | 0.070 | 0.084 | 0.100 | 0.120 | 0.140 | 0.160 | 0.185 | 0.210 |
| ISO h11 | 0.060 | 0.075 | 0.090 | 0.110 | 0.130 | 0.160 | 0.190 | 0.220 | 0.250 | 0.290 | 0.320 |
(Note: reordered into ascending diameter order — competitor tables are scrambled, which hurts readability and snippet capture.)
Super Duplex Steel Round Bar Weight Chart
While both are dual-phase steels, Super Duplex offers superior performance for extremely caustic conditions.
Metric Sizes
| Size | Kg / Mtr | Kg / Foot |
|---|---|---|
| 3 mm | 0.055 | 0.017 |
| 4 mm | 0.098 | 0.030 |
| 5 mm | 0.154 | 0.047 |
| 6 mm | 0.223 | 0.068 |
| 7 mm | 0.298 | 0.091 |
| 8 mm | 0.398 | 0.120 |
| 9 mm | 0.498 | 0.152 |
| 10 mm | 0.620 | 0.189 |
| 11 mm | 0.748 | 0.228 |
| 12 mm | 0.889 | 0.271 |
| 13 mm | 1.043 | 0.318 |
| 14 mm | 1.207 | 0.368 |
| 20 mm | 2.470 | 0.753 |
| 22 mm | 2.979 | 0.908 |
| 24 mm | 3.543 | 1.080 |
| 25 mm | 3.871 | 1.180 |
| 26 mm | 4.170 | 1.271 |
| 27 mm | 4.490 | 1.368 |
| 30 mm | 5.548 | 1.691 |
| 32 mm | 6.314 | 1.894 |
| 35 mm | 7.553 | 2.390 |
| 36 mm | 7.999 | 2.438 |
| 38 mm | 8.903 | 2.792 |
| 40 mm | 9.872 | 3.009 |
| 45 mm | 12.555 | 3.807 |
Imperial Sizes
| Size | Kg / Mtr | Kg / Foot |
|---|---|---|
| 1/8″ | 0.062 | 0.019 |
| 5/32″ | 0.095 | 0.029 |
| 3/16″ | 0.141 | 0.043 |
| 7/32″ | 0.190 | 0.058 |
| 1/4″ | 0.249 | 0.076 |
| 5/16″ | 0.387 | 0.118 |
| 3/8″ | 0.557 | 0.170 |
| 7/16″ | 0.761 | 0.232 |
| 1/2″ | 0.994 | 0.303 |
| 7/8″ | 3.038 | 0.926 |
| 1″ | 3.970 | 1.210 |
| 1-1/8″ | 5.033 | 1.534 |
| 1-1/4″ | 6.319 | 1.924 |
| 1-3/8″ | 7.550 | 2.303 |
| 1-1/2″ | 8.951 | 2.715 |
| 1-5/8″ | 10.449 | 3.200 |
| 1-3/4″ | 12.179 | 3.712 |
| 3″ | 35.762 | 10.900 |
| 3-1/4″ | 41.996 | 12.800 |
| 3-1/2″ | 48.772 | 14.850 |
| 3-3/4″ | 55.780 | 17.001 |
| 4″ | 63.340 | 19.306 |
| 4-1/4″ | 72.249 | 21.908 |
| 4-1/2″ | 80.340 | 24.487 |
| 4-3/4″ | 90.249 | 27.366 |
| 5″ | 99.940 | 30.461 |
| 5-1/2″ | 121.000 | 36.690 |
| 6″ | 143.900 | 43.860 |
| 6-1/2″ | 167.630 | 51.093 |
| 7″ | 196.000 | 59.432 |
| 7-1/2″ | 225.000 | 68.226 |
| 8″ | 254.550 | 77.586 |
| 10″ | 397.140 | 121.048 |
Also see: Nuts Weight Chart | Bolts Weight Chart
Super Duplex Stainless Steel Hex Bar Size Chart
| Size (mm A/F) | Weight (kg/m) | Size (mm A/F) | Weight (kg/m) |
|---|---|---|---|
| 7 × 7 | 0.337 | 22 × 22 | 3.324 |
| 8 × 8 | 0.440 | 24 × 24 | 3.956 |
| 9 × 9 | 0.556 | 25 × 25 | 4.292 |
| 10 × 10 | 0.687 | 26 × 26 | 4.642 |
| 11 × 11 | 0.831 | 28 × 28 | 5.384 |
| 12 × 12 | 0.989 | 30 × 30 | 6.181 |
| 13 × 13 | 1.161 | 32 × 32 | 7.032 |
| 14 × 14 | 1.346 | 34 × 34 | 7.939 |
| 15 × 15 | 1.545 | 36 × 36 | 8.900 |
| 16 × 16 | 1.758 | 50 × 50 | 17.168 |
| 17 × 17 | 1.985 | 53 × 53 | 19.290 |
| 18 × 18 | 2.225 | 55 × 55 | 20.774 |
| 19 × 19 | 2.479 | 60 × 60 | 24.723 |
| 20 × 20 | 2.747 | 65 × 65 | 29.015 |
| 21 × 21 | 3.029 | 70 × 70 | 33.650 |
| — | — | 75 × 75 | 38.629 |
Super Duplex Stainless Steel Rod Size Chart
| US Bar Size | Diameter (inch) | Metric Bar Size | Diameter (mm) | Japanese Bar Size | Diameter (mm) | ASTM/Canadian | Area (mm²) |
|---|---|---|---|---|---|---|---|
| #2 | 0.250 | 5 | 5 | 6 | 6 | 10M | 100 |
| #3 | 0.375 | 5.5 | 5.5 | 10 | 10 | 15M | 200 |
| #4 | 0.500 | 6 | 6 | 13 | 13 | 20M | 300 |
| #5 | 0.625 | 7 | 7 | 16 | 16 | 25M | 500 |
| #6 | 0.750 | 8 | 8 | 19 | 19 | 30M | 700 |
| #7 | 0.875 | 9 | 9 | 22 | 22 | 35M | 1000 |
| #8 | 1.000 | 10 | 10 | 25 | 25 | 45M | 1500 |
| #9 | 1.125 | 11 | 11 | 29 | 29 | 55M | 2500 |
| #10 | 1.250 | 12 | 12 | 32 | 32 | — | — |
| #11 | 1.375 | 14 | 14 | 35 | 35 | — | — |
| #12 | 1.500 | 16 | 16 | 38 | 38 | — | — |
| #13 | 1.625 | 18 | 18 | 41 | 41 | — | — |
| #14 | 1.750 | 20 | 20 | 44 | 44 | — | — |
Equivalent Grades of Super Duplex Round Bar
| Standard | UNS (North America) | Werkstoff Nr. (German) | EN | ASTM Forged |
|---|---|---|---|---|
| Super Duplex 2507 | S32750 | 1.4410 | X2CrNiMoN25-7-4 | F53 |
| Super Duplex | S32760 | 1.4501 | X2CrNiMoCuWN25-7-4 | F55 |
Super Duplex Round Bars HS Code
| Grade | HS Code |
|---|---|
| Super Duplex Round Bar | 72222099 |
Destructive & Non-Destructive Testing for Super Duplex Round Bars
Destructive Testing
- Tensile Testing
- Charpy V-Notch Impact Test
- Hardness Testing
- Fatigue Testing
- Fracture Toughness Testing
- Bend Test, Flaring & Flattening Test
- Micro Test / Macro Test
- Ferrite Content Measurement
Non-Destructive Testing
- Ultrasonic Testing (UT)
- Radiographic Testing (RT)
- Dye Penetrant Testing (DPT)
- Magnetic Particle Testing (MPT)
- Eddy Current Testing
- Positive Material Identification (PMI)
- Chemical / Spectro Analysis
Corrosion & Sour-Service Testing
- Pitting Resistance Test (ASTM G48)
- Intergranular Corrosion (IGC) Test
- Hydrogen-Induced Cracking (HIC), NACE TM0284
- Sulphide Stress Corrosion Cracking (SSC), NACE TM0177
- Hydrostatic Test
Finishes, Conditions, Documentation & Marking
Finishes: Black, Bright, Polished, Rough Turned, Peeled/Turned, No. 4, Matt, BA Surface roughness: 6 RA, 32 RA, 63 RA Conditions: Annealed, Solution Annealed, Hardened & Tempered, Precipitation Hardened Manufacturing route: Hot Rolled, Forged, Cold Drawn, Centreless Ground
Black-finish bars give a clean industrial appearance with an oxide layer; polished bars offer a smooth, reflective surface for decorative and sanitary use; bright bars are the choice for high-precision engineering, shafting and machining stock.
Marking on each bar: Material designation, grade, heat/lot code, size, standard, rating designation and Jade Alloys identification.
Applications of Super Duplex Steel Round Bars
Super duplex round bars are used where high mechanical strength must be paired with extreme corrosion resistance:
- Oil & Gas Industry: valves, pumps, pipeline components, downhole tooling, sour service
- Offshore & Subsea: risers, manifolds, umbilical components, seawater lift systems
- Marine & Shipbuilding: propeller shafts, seawater handling systems
- Desalination Plants: high-pressure pumps, RO plant hardware, flash chambers
- Chemical & Petrochemical Plants: reactors, heat exchangers, storage tanks, pressure vessels
- Pump & Valve Parts: pump shafts, impellers, valve stems, fasteners
- Power Generation & Flue-Gas Desulphurisation: scrubbers, FGD internals
- Pulp & Paper Industry: digesters, bleaching plant equipment
- Mining & Mineral Processing: slurry handling, acid leach circuits
- Construction & Structural Engineering: coastal and high-chloride structures
- Pharmaceutical & Pollution Control equipment
- Aerospace and valve manufacturing components
Related Products
Explore Our Other Round Bar Materials
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Frequently Asked Questions
1. What is a Super Duplex Steel Round Bar?
2. What is the difference between duplex and super duplex round bar?
3. Which grades of super duplex round bar does Jade Alloys supply?
4. What sizes are super duplex round bars available in?
5. What is the ASTM standard for super duplex round bar?
6. What is the maximum service temperature of super duplex stainless steel?
7. What is the difference between S32750 and S32760?
8. What is the weight of a 25 mm super duplex round bar?
9. Is super duplex round bar weldable?
10. What is the HS Code for super duplex round bar?
11. What tests and certificates are supplied with the bars?
12. What is the price of super duplex round bar in India?
Countries We Export Super Duplex Steel Round Bars To
Jade Alloys exports Super Duplex Steel Round Bars to more than 50 countries. Our regional sales representatives and stocking partners give buyers in these markets faster lead times and landed-cost pricing. See our full worldwide fastener & round bar supply network.
Get a Quote for Super Duplex Steel Round Bars
Looking for a trusted Super Duplex Steel Round Bar manufacturer, supplier and exporter? Jade Alloys supplies premium super duplex round bars, rods, hex bars, square bars, flat bars, bright bars and precision ground bars in all grades and finishes with complete material test certificates, export documentation and reliable worldwide delivery.
