When a major offshore platform struggled with rapid corrosion in sulfuric acid and seawater service, the answer wasn’t another round of costly maintenance but a material breakthrough: Alloy 31 Round Bars. These bars, engineered for the world’s harshest chemistries and most demanding clients, have become the backbone for engineers and procurement teams across process, marine, oil & gas, pharma, and power. Aurico Alloys LLP Alloy 31 Round Bars are the trusted choice for industries insisting on higher uptime, safer plants, and real lifecycle savings.
Table of Contents:
Alloy 31 (UNS N08031, DIN 1.4562) is an advanced iron-nickel-chromium-molybdenum super-austenitic alloy with stabilizing nitrogen and copper. Its formula closes the gap between typical high-alloy stainless steels and expensive nickel alloys, providing robust defence against sulfuric, phosphoric, hydrochloric acids, brine, and caustics way beyond the reach of 904L or Alloy 20. It excels in heat exchangers, digesters, piping, pressure vessels, and marine fittings where stress, temperature cycling, and chloride attack routinely challenge plant safety and compliance.
Aurico Alloys LLP offers Alloy 31 round bars per ASTM B649, EN 10028-7, and DIN 17752/17754, available from 6mm to 200mm, in bright, ground, or custom-finished form. They’re easy to weld, machine, and code-stamp for worldwide project needs. Each batch is supplied with mill test certificates, RoHS, REACH, EN 10204/3.1, and batch/lot traceability.
Alloy 31 maintains strength and toughness at cryogenic and elevated temperatures, showing yield ≥280 MPa, tensile ≥650 MPa, and elongation ≥40%. Its structure avoids sigma-phase embrittlement and delivers ISO-proven impact energy even at -196°C ideal for both extreme cold and heat service. By partnering with proven suppliers, hardware stores and OEMs ensure their customers’ safety and efficiency from first installation onward.
High-quality Alloy 31 Round Bars ready for industrial use.
Specification Overview
| Supplier & Manufacturer | Aurico Alloys LLP |
|---|---|
| Grade | Alloy 31 (UNS N08031, DIN 1.4562) |
| Standards | ASTM B649, EN 10028-7, DIN 17752/17754, ISO 9723 |
| Diameter Range | 6mm – 200mm |
| Length | 100mm – 6000mm |
| Finish | Bright, machined, ground, black, rough turned, cut to spec |
| Delivery | Direct stock, cut/fabbed, full MTC/report, export pack |
Equivalent Grades & Standards
| Property | Value |
|---|---|
| UNS number | N08031 |
| Werkstoff / EN number | 1.4562 |
| EN designation | X1NiCrMoCu32-28-7 |
| Density | 8.05 g/cm3 |
| Melting range | 1330-1370 °C |
| Modulus of elasticity (20 °C) | 198 GPa |
| Thermal conductivity (20 °C) | 11.7 W/m·K |
| Electrical resistivity (20 °C) | 104 µΩ·cm |
| Coefficient of expansion (100 °C) | 14.3 µm/m·°C |
| Magnetic permeability (relative - at 20 °C) | 1.001 |
| Rod and bar specification | ASTM B581 / B649 |
Identifiers and physical constants for Alloy 31. A dash means no such designation is published for this grade.
Stock & Product Availability
Alloy 31 round bars are stocked and supplied by Aurico Alloys LLP: diameters 6–200mm, lengths 100–6000mm, all MTC and global shipment ready for process plants, marine, pharma, energy, and repair needs.
Chemical Composition
| Element | Min (%) | Max (%) |
|---|---|---|
| Nickel (Ni) | 30.0 | 32.0 |
| Chromium (Cr) | 26.0 | 28.0 |
| Iron (Fe) | — | Balance |
| Sulfur (S) | — | 0.010 |
| Silicon (Si) | — | 0.3 |
| Manganese (Mn) | — | 2.0 |
| Phosphorus (P) | — | 0.020 |
| Molybdenum (Mo) | 6.0 | 7.0 |
| Copper (Cu) | 1.0 | 1.4 |
| Nitrogen (N) | 0.15 | 0.25 |
| Carbon (C) | — | 0.015 |
Composition limits for Alloy 31. These are specification limits for the grade, not measured values for a lot; the mill test certificate supplied with your order states the actual analysis.
Mechanical & Physical Properties
| Property | Typical Value |
|---|---|
| Tensile Strength (MPa) | ≥650 |
| Yield Strength, 0.2% MPa | ≥280 |
| Elongation (%) | ≥40 |
| Hardness (HB) | ≤230 |
| Impact Energy (-196°C) | ≥140 J/cm² |
| Max. Service Temp (°C) | up to 550–900 (solution annealed) |
Applications & Benefits
- Chemical: digesters, acid process equip, evaporation, FGD, high-acid lines
- Marine: pumps, scrubber piping, seawater condensers, desalination exchangers
- Oil & Gas: downhole tubes, umbilicals, sour service, phosphoric acid systems
- Pharma: sterilization, reactors, mixing, high-clean critical lines
- Power: condensers, turbines, heat exchangers in aggressive media or temp cycling
- Fabrication/Supply: precision-machined bars for hardware and urgent spares
FAQ & Search Trends
Global Export Destinations
We ship worldwide from Mumbai. See every destination we export to on our export markets page.
Domestic Supply Network Across India
We deliver across India from our Mumbai stockyard. See every city we supply on our supply locations page.
Conclusion
Alloy 31 Round Bars from Aurico Alloys LLP deliver proven resilience, machinability, and code-certification for process, marine, energy, and heavy industry enabling safer plants and better uptime where inferior bars wear out. Are your most demanding assets secured with next-generation Alloy 31 round bars?