Monel 400 Plate Price & Supplier in China – UNS N04400, Nickel-Copper Alloy
Monel 400 (UNS N04400) is a nickel-copper alloy with exceptional resistance to seawater, hydrofluoric acid, and alkaline media. If you are comparing Monel 400 plate price quotes from different Chinese suppliers, you need to understand what specifications drive the cost — and what quality differences separate competitive offers from mill-certified material.
Monel 400 Chemical Composition (UNS N04400 / W.Nr. 2.4360)
Monel 400 is a single-phase austenitic Ni-Cu solid solution alloy. Its composition is tightly controlled to deliver consistent corrosion performance:
- Nickel (Ni): 63.0–70.0%
- Copper (Cu): Remainder (approximately 28–34%)
- Iron (Fe): 2.5% max
- Manganese (Mn): 2.0% max
- Carbon (C): 0.30% max
- Silicon (Si): 0.5% max
- Sulfur (S): 0.024% max
Key Properties of Monel 400
- Seawater corrosion resistance: Corrosion rate < 0.025mm/year in stagnant and flowing seawater up to 40°C; widely used in marine hardware, condenser tubes, and seawater cooling systems
- Hydrofluoric acid resistance: Excellent resistance to non-aerated hydrofluoric acid at all concentrations and temperatures — the preferred material for hydrofluoric acid alkylation units in refineries
- Caustic alkali resistance: Immune to stress corrosion cracking in caustic soda (NaOH) and potash (KOH) solutions
- Mechanical properties: Tensile strength 480–700 MPa, yield strength 170–345 MPa, elongation 35–55%; can be cold-worked to increase strength
- Thermal conductivity: Approximately 21.8 W/m·K (vs 16.2 for 316L), beneficial in heat exchange applications
- Magnetic permeability: Low (接近非磁性), useful in electronic and instrumentation applications
Monel 400 Plate Specifications
| Parameter | Details |
|---|
| Standard | ASTM B127 / ASME SB-127, DIN/EN 10095 |
| UNS | N04400 |
| Thickness range | 0.5mm to 76mm |
| Width | Up to 2500mm; custom cut available |
| Length | Up to 6000mm (standard) or custom |
| Surface finish | 2B, BA, No.1 (hot rolled), ground, polished |
| Plate grades | Standard, premium (utlrasonic tested), nuclear |
Applications for Monel 400 Plates
- Marine & offshore: Seawater valves, pump impellers, ship hull plating, offshore platform hardware
- Oil & gas: Heat exchangers in refinery HF acid alkylation units, tubing for sour gas compression, downhole tools
- Chemical processing: Storage tanks for hydrofluoric acid, phosphoric acid evaporators, caustic handling vessels
- Power generation: Feedwater heaters, condensate pumps, steam turbine components in nuclear plants
- Pharmaceutical: Process vessels handling high-purity caustic and saline solutions
- Desalination: brine heaters, distillate lines, and evaporators in multi-stage flash plants
Monel 400 Plate Price Factors in 2026
When comparing Monel 400 plate price offers, consider these key price drivers:
- Nickel content: Monel 400 contains ~63–70% nickel — since nickel accounts for ~60–70% of raw material cost, any nickel price fluctuation directly impacts plate pricing
- Mill origin: Domestic Chinese mills (Gnee, TONGXIN) vs. imported (Special Metals, VDM) — imported VDM plate commands 30–50% premium over Chinese mill equivalents
- Ultrasonic testing (UT): Premium-sonic-tested plates (per ASTM B127) add USD 3–6/kg to base price but are mandatory for pressure vessel and marine applications
- Thickness tolerance: Tight thickness tolerance (ASTM B127 ±10%) vs. commercial tolerance affects yield and pricing
- Order quantity: 1–5 sheets: full mill price; 10+ sheets: 5–12% volume discount; full container (15–20MT): best unit price
- Surface condition: Ground & polished plates (Ra ≤ 0.4μm) carry 15–25% premium over standard 2B finish
Typical Monel 400 Plate Price Range (2026)
Domestic Chinese mill (ASTM B127, 3–20mm): USD 28–55/kg
Imported VDM/Special Metals (same specs): USD 45–85/kg
UT-tested, certificate-grade: Add USD 4–8/kg to above
Prices are indicative and subject to LME nickel spot price. Request a firm offer with your exact specs for accurate pricing.
Frequently Asked Questions – Monel 400 Plate Sourcing
What is the difference between Monel 400 and Monel K500?
Monel 400 is a solid solution Ni-Cu alloy (63% Ni, 28–34% Cu) — cannot be hardened by heat treatment. Monel K500 (UNS N05500) adds aluminum (2.3–3.15%) and titanium (0.35–0.85%) and can be precipitation-hardened to ~130 ksi tensile strength while retaining corrosion resistance. K500 is used for pump shafts, propeller shafts, and fasteners requiring higher strength. For standard seawater and acid service, 400 is more cost-effective.
Is Monel 400 magnetic?
Monel 400 is essentially non-magnetic in the annealed condition (magnetic permeability 𐐽1.01). Cold working slightly increases permeability. This makes it suitable for electronic and instrumentation applications where magnetic interference must be minimized.
Can Monel 400 be welded?
Yes. Monel 400 welds by GTAW (TIG) with Monel 60 (ERNiCu-7) or AWS A5.14 filler, or by SMAW (stick) with Monel 190 or 197 electrodes. No preheat or post-weld heat treatment is required. The weld deposit retains the corrosion resistance of the base metal. We offer fabrication services with ASME-certified welders.
What certificates come with Monel 400 plates?
Standard supply includes EN 10204 3.1 type certificates with actual chemical composition (spectrometer-tested) and mechanical properties (tensile, yield, elongation, hardness) from the mill. For pressure equipment, we can also provide NACE MR0175 compliance certificates, PED 2014/68/EU documents, and full traceability from heat number to raw material lot.
What is the lead time for Monel 400 plates from China?
Common thicknesses (3–12mm) from domestic stock: 5–8 working days. Mill orders for non-stock sizes: 20–35 working days. Full container sea freight to major ports: 25–45 days depending on destination. Airfreight available for urgent needs within 5–10 days (higher cost).