Monel 400

Monel 400 is a nickel-copper alloy known for its excellent corrosion resistance in seawater, together with good strength and toughness. It performs reliably in marine environments and many chemical media, making it widely used in marine, offshore, chemical-processing, and oil & gas equipment.

Appearance & Properties

Color: Silver-gray to silvery white

Density: Approx. 8.8 g/cm³

Tensile Strength: Typically approx. 480–620 MPa, depending on material condition

Corrosion Resistance: Excellent

Seawater Resistance: Excellent

Machinability: Difficult

Toughness: Good

Weldability: Good

Magnetism: Generally somewhat magnetic

Surface Finishes: Blasting, polishing, passivation, grinding, etc.

Typical Applications

Monel 400 is widely used in marine, offshore, chemical processing, oil and gas, pumps and valves, heat exchangers, and industrial fluid-handling systems.

Typical parts include valve components, pump shafts, impellers, pipe fittings, flanges, fasteners, heat-exchanger components, and seawater-resistant precision CNC parts.

Advantages

• Excellent seawater corrosion resistance

• Good strength and toughness

• Good resistance to many acids, alkalis, and salt solutions

• Maintains useful mechanical properties across a wide temperature range

• Particularly suitable for marine and chemical environments

Limitations

• Difficult to CNC machine

• Strong tendency to work harden

• Higher material cost than conventional stainless steels

• Not suitable for all strongly oxidizing chemical environments