Alloy 31 plate supplier. Contact us to get free quote and sample!
Alloy 31 is an austenitic super stainless steel based on an iron-nickel-chromium-molybdenum base. The synergistic effects of high chromium, high molybdenum, copper additions, and nitrogen additions give Nickel Alloy 31 a near-perfect balance of properties, enabling it to operate effectively in both oxidizing and reducing environments. HT PIPE is a alloy 31 plate supplier with 15+ export experience. Contact us for more information and quotes for free!
alloy 31 astm Uniform Corrosion Resistance
- Sulfuric Acid: Excellent performance in all concentrations and temperatures up to 60°C, primarily due to the addition of copper.
- Phosphoric Acid: Resistant to a wide range of phosphoric acid concentrations, especially in processes containing impurities such as fluoride.
- Chloride Media: Performance far exceeds that of conventional stainless steels, such as FeCl₃ and CuCl₂.
- Organic Acids: Such as formic acid and acetic acid.
- Alkaline Solutions: Resistant to caustic soda corrosion.
Technical Specifications & Standard Compliance
HT PIPE supplies Alloy 31 plates, sheets, seamless pipes, flanges, and pipe fittings according to international manufacturing standards:
| Specification Type | International Standards |
| Plate, Sheet & Strip | ASTM B625 / ASME SB625, DIN 17750, EN 10028-7 |
| Seamless & Welded Pipe/Tube | ASTM B677, ASTM B673, ASTM B674 / ASME SB677 |
| Bar, Rod & Wire | ASTM B649 / ASME SB649, DIN 17752 |
| Forgings & Flanges | ASTM B564 / ASME SB564 |
alloy 31 uns n08031 Weldability
All common welding methods are acceptable, including tungsten inert gas welding (TIG/GTAW), metal inert gas welding (MIG/GMAW), and metal arc welding (SMAW). The use of compatible welding consumables (such as ERNiCrMo-11) is recommended. Its low hot crack susceptibility and excellent post-weld corrosion resistance ensure the reliability of the welded joint area.
nickel alloy 31 plate Formability
As a sheet material, it exhibits good cold and hot forming capabilities, allowing for operations such as stamping, rolling, and bending. However, its higher strength requires greater processing forces, which should be considered when designing molds and processing equipment.
Why choose Alloy 31 over other materials?
- vs. 316L/317L: Alloy N08031's corrosion resistance is comparable to that of other materials, especially in chloride-containing environments, where the latter are susceptible to pitting and stress corrosion cracking.
- vs. 904L (N08904): Alloy 31 significantly outperforms 904L in mechanical strength, pitting resistance, and sulfuric acid corrosion resistance, and boasts a higher PREN value.
- vs. 6-Mo super-austenitic steels (such as 254SMO and AL-6XN): Alloy 31 offers comparable pitting corrosion resistance, but due to its copper content, it performs better in reducing media, particularly sulfuric acid, and exhibits higher strength.
- vs. Nickel-based alloys such as Hastelloy C-276 (N10276): Alloy N08031 offers comparable performance in many moderately severe corrosive environments, but at a significantly lower cost (based on an iron-nickel base with a lower nickel content), offers higher mechanical strength, and is easier to process. This makes it an ideal alternative to expensive nickel-based alloys for cost reduction and efficiency gains.
| Material Grade | UNS / W.Nr. | PREN Value | Sulfuric Acid Performance | Chloride Pitting Resistance | Relative Cost Efficiency |
| Alloy 31 | UNS N08031 / 1.4562 | ≥ 48 | Outstanding (0-100% Conc.) | Superior | High (Cost-Effective vs. Ni-Alloys) |
| 316L | UNS S31603 / 1.4404 | ~25 | Low | Low (Prone to Pitting) | Standard / Commodity |
| 904L | UNS N08904 / 1.4539 | ~34 | Moderate | Moderate | Moderate |
| 254 SMO | UNS S31254 / 1.4547 | ~43 | Moderate in Reducing Media | High | High |
| Hastelloy C-276 | UNS N10276 / 2.4819 | ≥ 64 | Extreme | Extreme | Premium / High Cost |
Cost Reduction Alternative to High-Nickel Alloys (Hastelloy C-276)
While nickel-base alloys like Hastelloy C-276 offer extreme corrosion resistance, their high nickel content (~57%) makes them expensive and vulnerable to nickel market volatility. Alloy 31 serves as an ideal iron-nickel-base alternative:
Lower Raw Material Cost: Delivers near-equivalent performance in moderately severe acidic media at a significantly lower cost per ton.
Higher Mechanical Strength: Alloy 31 features yield strength (~300 MPa) higher than standard austenitic grades, enabling thinner wall designs in piping and vessel fabrication.
application uns n08031 sheet
- Chemical process industries: Sulfuric acid coolers, reactors, evaporators, piping, and vessels, phosphoric acid production equipment, and chlorine-containing organic synthesis units.
- Oil & Gas: Scrubbers, absorbers, heat exchanger plates, and flues used in oil and gas field environments high in CO₂, H₂S, and chloride ions (especially in "wet" FGD systems).
- Desalination & Offshore: High-pressure piping and evaporators in desalination plants, key components on offshore platforms.
- Pollution Control: Critical components of flue gas desulfurization (FGD) systems in waste incineration plants and power plants, such as scrubbers and reheaters.
- Pharmaceutical & Food: Equipment requiring extremely high cleanliness and corrosion resistance.
