Monel 400丨UNS N04400
Monel 400 (UNS N04400 / W.Nr. 2.4360) is a nickel-copper alloy known for its exceptional resistance to seawater, hydrofluoric acid, alkalis, and reducing environments. It combines excellent corrosion resistance with high strength and good weldability, making it ideal for marine engineering, chemical processing, oil & gas, and heat exchanger applications. Available in pipe, tube, plate, sheet, bar, wire, and forging forms.
✔ ASTM / ASME Standards ✔ Fast Delivery
✔ Global Export ✔ Custom Sizes
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Monel 400 Supplier & Manufacturer
Monel 400 (UNS N04400 / W.Nr. 2.4360) is a solid-solution nickel-copper alloy offering outstanding resistance to seawater, hydrofluoric acid, alkalis and reducing chemical environments. The alloy combines excellent corrosion resistance with high mechanical strength and good fabrication properties.
Monel 400 is widely used in marine engineering, chemical processing, offshore oil & gas, heat exchangers, pumps, valves and desalination systems where long-term corrosion resistance is critical.
JA Alloy supplies premium Monel 400 products including pipe, tube, plate, sheet, bar, wire, flange and forgings manufactured according to ASTM, ASME and international standards.
Key Features of Monel 400
- Exceptional seawater corrosion resistance
- Excellent resistance to hydrofluoric acid
- Superior performance in alkali environments
- Outstanding resistance to stress corrosion cracking
- High strength and toughness
- Good weldability and fabrication properties
- Suitable for marine and offshore applications
- Long service life in aggressive environments
Chemical Composition of Monel 400
| Element | Composition (%) |
|---|---|
| Nickel (Ni) | 63.0 min |
| Copper (Cu) | 28.0 – 34.0 |
| Iron (Fe) | 2.5 max |
| Manganese (Mn) | 2.0 max |
| Carbon (C) | 0.30 max |
| Silicon (Si) | 0.50 max |
| Sulfur (S) | 0.024 max |
Mechanical Properties of Monel 400
| Property | Value |
|---|---|
| Tensile Strength | 550 MPa min |
| Yield Strength | 240 MPa min |
| Elongation | 35% min |
| Hardness | ≤ 65 HRB |
| Density | 8.80 g/cm³ |
| Melting Range | 1300 – 1350°C |
Corrosion Resistance
Monel 400 exhibits excellent resistance to flowing seawater, brackish water, hydrofluoric acid, sulfuric acid and alkaline solutions. The alloy performs particularly well in reducing environments where stainless steels may fail.
Its superior resistance to seawater corrosion makes it one of the most widely used alloys in marine engineering and offshore applications.
When Should You Choose Monel 400?
Choose Monel 400 when:
- Seawater corrosion resistance is required
- Hydrofluoric acid service is involved
- Marine environments are present
- Excellent resistance to alkalis is needed
- Long-term reliability in offshore systems is critical
Applications of Monel 400
Marine Engineering
Propeller shafts, seawater piping, marine fasteners and offshore platforms.
Chemical Processing
Hydrofluoric acid handling systems, chemical reactors and process equipment.
Oil & Gas
Offshore production equipment, valves and piping systems.
Heat Exchangers
Condenser tubes and heat exchanger components operating in seawater service.
Monel 400 vs Stainless Steel 316
| Property | Monel 400 | 316 Stainless Steel |
|---|---|---|
| UNS Number | N04400 | S31600 |
| Main Composition | Ni-Cu | Fe-Cr-Ni-Mo |
| Seawater Resistance | Excellent | Good |
| Hydrofluoric Acid Resistance | Excellent | Poor |
| Strength | Higher | Moderate |
| Stress Corrosion Cracking Resistance | Excellent | Moderate |
| Marine Applications | Excellent | Good |
| Cost | Higher | Lower |
| Best For | Seawater, Marine & HF Acid Service | General Industrial Applications |
When selecting between Monel 400 and 316 stainless steel, Monel 400 is generally preferred for seawater systems, marine hardware, hydrofluoric acid service and offshore applications where superior corrosion resistance is required. While 316 stainless steel offers a lower initial cost, Monel 400 often provides a longer service life and reduced maintenance costs in aggressive environments.
Frequently Asked Questions
What is Monel 400 used for?
Monel 400 is widely used in marine engineering, chemical processing, offshore oil & gas and heat exchanger applications.
Is Monel 400 resistant to seawater?
Yes. Monel 400 is one of the best-performing alloys in flowing seawater environments.
Is Monel 400 better than stainless steel?
For seawater and hydrofluoric acid service, Monel 400 generally provides significantly better corrosion resistance than stainless steel.
Can Monel 400 be welded?
Yes. Monel 400 has excellent weldability using conventional welding techniques.
Why Choose J&A Alloy as Your Monel 400 Supplier?
- Professional nickel alloy manufacturer
- ASTM / ASME compliant materials
- Strict PMI and quality inspection
- Global export experience
- Fast delivery and competitive pricing
- Technical support and material selection assistance
Contact J&A Alloy today for Monel 400 pricing, datasheets, and technical support.
