Incoloy 825丨UNS N08825
Incoloy 825, known as UNS N08825, is a nickel-iron-chromium alloy with additions of molybdenum, copper, and titanium, providing outstanding resistance to sulfuric acid, phosphoric acid, seawater, and chloride-containing environments.
J&A Alloy supplies Incoloy 825 pipe, tube, plate, sheet, bar, wire, fittings, and flanges in accordance with ASTM and ASME standards.
✓ Excellent acid corrosion resistance
✓ Resistant to chloride stress corrosion cracking
✓ Good high-temperature performance
✓ Available in pipe, tube, plate, sheet and bar
Incoloy 825 Supplier | UNS N08825 Nickel Alloy
Incoloy 825 (UNS N08825, W.Nr. 2.4858) is a nickel-iron-chromium alloy enhanced with molybdenum, copper and titanium. This unique composition provides exceptional resistance to both reducing and oxidizing acids, making it one of the most versatile corrosion-resistant alloys for chemical processing and marine applications.
The alloy offers outstanding resistance to sulfuric acid, phosphoric acid, seawater, chloride-containing environments and stress corrosion cracking. Its titanium stabilization minimizes sensitization during welding, ensuring long-term corrosion resistance in fabricated equipment.
J&A Alloy supplies Incoloy 825 products in pipe, tube, plate, sheet, bar, wire, fittings, flanges and forgings with complete traceability and international standard compliance.
Key Features of Incoloy 825
- Excellent resistance to sulfuric acid
- Outstanding resistance to phosphoric acid
- Resistant to chloride stress corrosion cracking
- Superior resistance to pitting and crevice corrosion
- Good oxidation resistance
- Excellent weldability
- Stable microstructure after welding
- Suitable for marine and offshore environments
- Good mechanical strength up to 1000°F (538°C)
Chemical Composition of Incoloy 825
| Element | Content (%) |
|---|---|
| Nickel (Ni) | 38.0 – 46.0 |
| Chromium (Cr) | 19.5 – 23.5 |
| Iron (Fe) | Balance |
| Molybdenum (Mo) | 2.5 – 3.5 |
| Copper (Cu) | 1.5 – 3.0 |
| Titanium (Ti) | 0.6 – 1.2 |
| Carbon (C) | ≤ 0.05 |
| Manganese (Mn) | ≤ 1.0 |
| Silicon (Si) | ≤ 0.5 |
| Sulfur (S) | ≤ 0.03 |
Mechanical Properties of Incoloy 825
| Property | Value |
|---|---|
| Tensile Strength | ≥ 585 MPa (85 ksi) |
| Yield Strength (0.2%) | ≥ 240 MPa (35 ksi) |
| Elongation | ≥ 30% |
| Hardness | ≤ HRB 90 |
| Density | 8.14 g/cm³ |
| Melting Range | 1370–1400°C |
Corrosion Resistance
Incoloy 825 is designed specifically for aggressive chemical environments.
Excellent Resistance To:
- Sulfuric Acid
- Phosphoric Acid
- Nitric Acid
- Organic Acids
- Seawater
- Brine Solutions
- Chloride Environments
Resistant To:
- Pitting Corrosion
- Crevice Corrosion
- Stress Corrosion Cracking
- Intergranular Corrosion
The alloy performs exceptionally well where stainless steels fail due to acid attack.
High Temperature Performance
Incoloy 825 maintains excellent mechanical strength and oxidation resistance at elevated temperatures.
Benefits include:
- Oxidation resistance up to approximately 540°C
- Stable microstructure
- Good creep resistance
- Thermal fatigue resistance
- Long-term reliability in heat exchangers and process equipment
Available Forms
J&A Alloy supplies Incoloy 825 in:
- Seamless Pipe
- Welded Pipe
- Seamless Tube
- Welded Tube
- Plate
- Sheet
- Coil
- Round Bar
- Flat Bar
- Hex Bar
- Wire
- Pipe Fittings
- Flanges
- Forgings
Custom dimensions available upon request.
Applications of Incoloy 825
Chemical Processing
- Acid production equipment
- Heat exchangers
- Pressure vessels
- Storage tanks
Oil & Gas
- Sour gas equipment
- Offshore piping systems
- Wellhead components
Marine Engineering
- Seawater cooling systems
- Desalination plants
- Offshore structures
Pollution Control
- FGD systems
- Scrubbers
- Waste treatment facilities
Nuclear Industry
- Fuel reprocessing equipment
- Chemical handling systems
Incoloy 825 vs Stainless Steel 316L
| Property | Incoloy 825 | Stainless Steel 316L |
|---|---|---|
| Nickel Content | 38–46% | 10–14% |
| Sulfuric Acid Resistance | Excellent | Moderate |
| Chloride SCC Resistance | Excellent | Moderate |
| Pitting Resistance | Excellent | Good |
| Seawater Resistance | Excellent | Good |
| High Temperature Performance | Excellent | Good |
| Cost | Higher | Lower |
Choose Incoloy 825 When:
- Acid service is critical
- Chloride SCC resistance is required
- Long service life is essential
Choose 316L When:
- Corrosion conditions are moderate
- Budget is the primary consideration
Welding & Fabrication
Incoloy 825 can be readily fabricated using conventional methods.
Suitable processes:
- GTAW (TIG)
- GMAW (MIG)
- SMAW
- SAW
Advantages:
- Excellent weldability
- Resistant to sensitization
- Good post-weld corrosion resistance
- No special heat treatment typically required
Standards & Equivalent Grades
| Standard | Grade |
|---|---|
| UNS | N08825 |
| W.Nr. | 2.4858 |
| ASTM | B423 |
| ASTM | B424 |
| ASTM | B425 |
| ASTM | B564 |
| ASTM | B705 |
| ASME | SB423 |
| ASME | SB424 |
| ASME | SB425 |
Equivalent Names
- Incoloy 825
- Alloy 825
- UNS N08825
- W.Nr. 2.4858
Frequently Asked Questions
What is Incoloy 825 used for?
Incoloy 825 is widely used in chemical processing, oil & gas, marine engineering, pollution control and acid production facilities.
Is Incoloy 825 resistant to sulfuric acid?
Yes. Incoloy 825 was specifically developed to provide excellent resistance to sulfuric acid and phosphoric acid.
Can Incoloy 825 be welded?
Yes. The alloy has excellent weldability and maintains corrosion resistance after welding.
What is the difference between Incoloy 825 and 316L?
Incoloy 825 contains significantly more nickel and molybdenum, providing superior resistance to acids and chloride stress corrosion cracking.
Is Incoloy 825 suitable for seawater?
Yes. It provides excellent resistance to seawater corrosion, pitting and crevice attack.
Why Choose J&A Alloy
✓ ASTM / ASME compliant materials
✓ Full PMI and material traceability
✓ Third-party inspection available
✓ Competitive factory-direct pricing
✓ Global shipping support
✓ Custom dimensions available
✓ Experienced nickel alloy supplier
Whether you require Incoloy 825 pipe, tube, plate, sheet, bar, fittings, or forgings, J&A Alloy provides reliable corrosion-resistant material solutions for demanding industrial applications.
