Home > Forged Bars > Duplex & Super Duplex Forged Bars
Grades: UNS S31803 (Duplex 2205), UNS S32750 (Super Duplex 2507)
Inox Steel India is a trusted manufacturer, supplier, and exporter of Duplex & Super Duplex Forged Bars, supplying high-performance forged solutions in UNS S31803 (Duplex 2205) and UNS S32750 (Super Duplex 2507) to industries across India, GCC, Middle East, Africa, Europe, and North & South America.
Duplex and super duplex stainless steel forged bars are specifically engineered for high-strength, corrosion-critical, and chloride-rich environments, where conventional austenitic stainless steels are not sufficient. Their dual-phase microstructure (austenitic + ferritic) delivers exceptional mechanical strength, superior resistance to stress corrosion cracking (SCC), and long service life in aggressive service conditions.
At Inox Steel India, duplex forged bars are produced using controlled hot forging followed by solution annealing, ensuring optimal phase balance, corrosion resistance, and full compliance with ASTM, ASME, and EN standards.
🔧 What Are Duplex & Super Duplex Forged Bars?
Duplex and super duplex forged bars are solid stainless steel sections manufactured by hot forging duplex-grade billets under high compressive force, followed by precise heat treatment to maintain the correct ferrite–austenite balance.
Compared to conventional stainless steel grades, duplex forged bars offer:
These properties make duplex forged bars the preferred material for offshore, marine, oil & gas, chemical processing, and desalination applications.
1️⃣ Billet Selection
Certified duplex and super duplex billets conforming to UNS S31803 / S32205 and UNS S32750 chemistry are selected from approved mills.
2️⃣ Hot Forging
Billets are forged using open-die or closed-die forging, ensuring directional grain flow and internal structural integrity.
3️⃣ Solution Annealing
Forged bars are solution annealed to restore corrosion resistance and achieve the required 35–55% ferrite balance.
4️⃣ Rough Machining (Optional)
Bars can be supplied in rough-machined condition to reduce CNC machining time.
5️⃣ Inspection & Testing
Each forged bar undergoes UT, PMI, ferrite measurement, and mechanical testing before dispatch.
⭐ Key Advantages of Duplex & Super Duplex Forged Bars
✔ Nearly double yield strength compared to austenitic stainless steel
✔ Exceptional resistance to pitting, crevice corrosion & SCC
✔ High fatigue strength for cyclic loading
✔ Reliable performance in seawater and chloride-rich media
✔ Reduced wall thickness possible due to higher strength
✔ Long service life in extreme environments
MASTER TECHNICAL DATASHEET – DUPLEX & SUPER DUPLEX FORGED BARS
Grades: UNS S31803 (Duplex 2205) · UNS S32750 (Super Duplex 2507) | Inox Steel India
| Parameter | Duplex 2205 – S31803 Forged Bars | Super Duplex 2507 – S32750 Forged Bars |
|---|---|---|
| Material Type | Duplex Stainless Steel (Austenitic + Ferritic) | Super Duplex Stainless Steel |
| Standard / Specification | ASTM A182 / A276 | ASTM A182 / A276 |
| UNS Designation | S31803 / S32205 | S32750 |
| Chromium Content | ~22% Cr | ~25% Cr |
| Product Form | Forged Bars | Forged Bars |
| Forging Process | Open Die / Closed Die Forging | Open Die / Closed Die Forging |
| Supply Condition | Solution Annealed | Solution Annealed |
| Diameter Range | 40 mm – 750 mm | 40 mm – 650 mm |
| Length | Random / Cut Lengths | Random / Cut Lengths |
| Yield Strength (MPa) | ≥ 450 MPa | ≥ 550 MPa |
| Tensile Strength (MPa) | ≥ 620 MPa | ≥ 800 MPa |
| Elongation (%) | ≥ 25% | ≥ 25% |
| PREN (Pitting Resistance) | ~35 | ≥ 40 |
| Corrosion Resistance | Excellent (Chloride & SCC) | Exceptional (Severe Chloride) |
| Temperature Service | Up to 300 °C | Up to 300 °C |
| Creep Resistance | High | Very High |
| Ferrite Content | 35 – 55% | 35 – 55% |
| Machinability | Moderate | Moderate |
| Testing Performed | UT, PMI, Mechanical, Ferrite | UT, PMI, Mechanical, Ferrite, ASTM G48 |
| Inspection Standard | ASTM / ASME | ASTM / ASME |
| Certification | EN 10204 3.1 / 3.2 | EN 10204 3.1 / 3.2 |
| Typical End Use | Offshore, Marine, Process Equipment | Subsea, Desalination, Oil & Gas |
| HS / HSN Code | 7222 / 7228 | 7222 / 7228 |
🔹 Duplex 2205 Forged Bars – UNS S31803
Duplex 2205 offers an ideal balance of strength, corrosion resistance, and cost efficiency. It is widely used in offshore platforms, chemical reactors, pressure vessels, and heat exchangers exposed to chlorides.
🔹 Super Duplex 2507 Forged Bars – UNS S32750
Super Duplex 2507 provides very high strength and exceptional pitting resistance (PREN ≥ 40). It is the preferred choice for subsea equipment, desalination plants, seawater systems, and critical oil & gas components.
🌍 Global & Indian Demand Insight
In India, duplex forged bars are increasingly used in offshore oil & gas, fertilizer plants, refineries, and desalination projects, especially around Mumbai, Hazira, and coastal industrial zones.
International demand includes:
Inox Steel India supports global supply with ready inventory and export dispatch via JNPT, Mundra, and Hazira ports.
Duplex & Super Duplex Forged Bars – Applications, Sizes, Pricing & Quality
Duplex & Super Duplex Forged Bars supplied by Inox Steel India are engineered for high-strength, corrosion-intensive, and chloride-rich service conditions, where failure risk must be minimized. Each grade is selected based on pitting resistance, operating pressure, temperature limits, and fatigue loading, ensuring long-term reliability in critical environments.
🔹 Duplex 2205 Forged Bars (UNS S31803 / S32205)
Service Focus: High strength with excellent corrosion resistance
Typical Applications:
Industries Served:
Oil & Gas | Chemical Processing | Marine | Offshore | Power & Energy
🔹 Super Duplex 2507 Forged Bars (UNS S32750)
Service Focus: Severe chloride and high-pressure service
Typical Applications:
Industries Served:
Offshore Oil & Gas | Marine | Desalination | Petrochemical | Energy Infrastructure
Inox Steel India supplies duplex and super duplex forged bars in standard as well as custom-engineered sizes, suitable for rough machining or precision CNC operations.
| Form | Size Range |
|---|---|
| Forged Round Bars | 40 mm – 750 mm Ø |
| Forged Square Bars | 40 mm – 550 mm |
| Forged Flat Bars | Up to 600 mm width |
| Custom Forged Shapes | As per drawings |
| Rough Machined Bars | As per machining allowance |
📌 Custom cut lengths, machining allowance, and near-net forgings available on request.
💰 Duplex & Super Duplex Forged Bars – Indicative Price Range (2025)
| Grade | Price Range (INR / Kg) | Price Range (USD / Kg) | Remarks |
|---|---|---|---|
| Duplex 2205 (S31803) | ₹ 420 – ₹ 550 | $ 5.05 – $ 6.65 | High strength & corrosion resistance |
| Super Duplex 2507 (S32750) | ₹ 650 – ₹ 850 | $ 7.85 – $ 10.25 | Severe chloride resistance |
🧾 Prices depend on size, heat treatment, testing (ASTM G48), machining, and order volume.
🔢 HS / HSN Code – Duplex & Super Duplex Forged Bars
All duplex and super duplex forged bars supplied by Inox Steel India undergo stringent metallurgical and corrosion testing.
Standard Tests Conducted:
✔ Ultrasonic Testing (UT)
✔ Positive Material Identification (PMI)
✔ Ferrite Content Measurement
✔ Tensile, Yield & Elongation Tests
✔ Hardness Testing
✔ ASTM G48 Pitting & Crevice Corrosion Test (Super Duplex)
✔ Dimensional & Visual Inspection
Optional Third-Party Inspection:
SGS · TUV · BV · DNV · Lloyd’s
All materials are supplied with EN 10204 3.1 / 3.2 Mill Test Certificates.
🚢 Packaging & Export Readiness
Ports of Dispatch: JNPT (Mumbai) · Mundra · Hazira
Inox Steel India is a preferred manufacturer, supplier, and exporter of duplex and super duplex forged bars, trusted for high-strength and corrosion-critical applications where material failure is not acceptable.
Our key strengths include:
✔ Approved forging mills with strict chemistry & phase balance control
✔ Expertise in solution annealing for optimal ferrite–austenite ratio
✔ Supply of large-diameter forgings with sound internal structure
✔ Full compliance with ASTM, ASME, EN & NACE requirements
✔ EN 10204 3.1 / 3.2 certification with complete traceability
✔ Competitive pricing for domestic & international projects
✔ Proven export record across offshore and marine sectors
We focus on delivering forged duplex materials that perform reliably in chloride-rich, high-pressure, and aggressive environments.
🧩 Industries & Applications Served
| Industry | Application | Preferred Grade |
|---|---|---|
| Offshore Oil & Gas | Risers, connectors, manifolds | Super Duplex S32750 |
| Marine Engineering | Shafts, seawater components | Duplex S31803 |
| Desalination Plants | High-pressure pumps & piping | Super Duplex S32750 |
| Chemical Processing | Reactors, vessels, heat exchangers | Duplex S31803 |
| Petrochemical | Corrosion-resistant pressure parts | Duplex / Super Duplex |
| Energy Infrastructure | Structural & process components | Duplex S31803 |
| Subsea Systems | Wellhead & subsea equipment | Super Duplex S32750 |
Yes. Duplex forged bars have nearly double the yield strength of SS 316. Correct ferrite balance (35–55%) ensures optimal strength, corrosion resistance, and toughness. Yes. ASTM G48 pitting and crevice corrosion testing is conducted for super duplex grades. Yes. Duplex and super duplex grades are ideal for seawater and offshore applications. Yes. We regularly export to GCC, Europe, Africa, and the Americas. Are duplex forged bars stronger than SS 316?
Why is ferrite content important in duplex forged bars?
Do you perform ASTM G48 testing?
Are duplex forged bars suitable for seawater service?
Do you export duplex & super duplex forged bars?