Alloy 400 and Monel 400 refer to the same material - a nickel-copper alloy with excellent corrosion resistance, especially in seawater and chemical environments.
✅ Comparison Table: Alloy 400 vs Monel 400
| Term | Description |
|---|---|
| Alloy 400 | Generic name for the nickel-copper alloy with UNS number N04400. |
| Monel 400 | Trademarked name by Special Metals Corporation for Alloy 400. |
| UNS Number | N04400 (used for both names) |
| Standards | ASTM B127 (sheet), ASTM B165 (tube), ASTM B164 (bar), etc. – same for both. |
| Composition | ~63% Nickel, ~28–34% Copper, with small amounts of iron, manganese, carbon, silicon. |
| Properties | High strength, excellent corrosion resistance, non-magnetic, good weldability and ductility – identical for both names. |
| Usage | Marine, chemical, heat exchanger, aerospace, and oil & gas industries. |
| Difference | Only the name/trademark – "Monel 400" is the branded version; "Alloy 400" is the generic equivalent. |
🔧 In Practice:
If you're sourcing material, "Alloy 400" is often used as a general designation.
If the client or project requires a specific mill origin or branded product, they may specify "Monel 400".
Both conform to the same ASTM and UNS standards.
If needed, SSM can supply Monel 400 or Alloy 400 products with full certification (e.g., ASTM B165 / B127, EN 10204 3.1, and optional brand traceability). Let me know if you need a supplier declaration or branding clarification for customer assurance.
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