Monel 400 Round Bars — ASTM B164 UNS N04400 Supplier & Exporter
Jade Alloys is a Mumbai-based manufacturer, supplier, and exporter of ASTM B164 UNS N04400 Monel 400 Round Bars, supplying EN 10204 3.1 mill-certified bar stock to clients across 50+ countries. Our inventory covers diameters from 3 mm to 800 mm in round, hex, flat, square, and hollow profiles available in annealed, cold-drawn, and forged conditions. Whether you need alloy 400 bar for a marine shaft application, a pump housing in a chemical processing plant, or a NACE-compliant wellhead component, we hold ready stock in Mumbai and dispatch the same week. Every order is traceable to the melt heat number and accompanied by a full EN 10204 3.1 Mill Test Certificate.
Monel 400 bar is also supplied in Monel 400 Sheets and Plates, Monel 400 Pipes and Tubes, and Monel 400 Tube Plugs for heat exchanger applications.
What Are Monel 400 Round Bars?
Monel 400 is a nickel-copper alloy containing at least 63% nickel and 28 to 34% copper, with small additions of iron, manganese, carbon, and silicon (UNS N04400 / Werkstoff Nr. 2.4360). It is the most widely used grade in the Monel alloy family, recognised for outstanding corrosion resistance across marine, chemical processing, oil and gas, and aerospace environments. The alloy resists seawater, hydrochloric acid, hydrofluoric acid when de-aerated, alkalis, and a wide range of organic and inorganic compounds.
Monel 400 is a solid-solution alloy whose strength cannot be increased by heat treatment and can only be improved through cold working. This makes it dimensionally stable and highly predictable in machined applications, which is a key reason engineers specify it for pump shafts, valve stems, and precision-turned components.
Unlike austenitic stainless steels, Monel 400 does not suffer stress-corrosion cracking in chloride environments, a critical advantage in offshore, desalination, and chemical processing applications where 316L stainless steel fails. The alloy also resists microbially induced corrosion (MIC), making it the standard specification for underwater structures, offshore platform components, and submerged pump systems where biological fouling accelerates degradation in lesser alloys.
Monel 400 Round Bars are rated for continuous service up to 480°C (900°F). The alloy is attacked in sulfur-bearing gases above approximately 370°C (700°F) and should not be used with molten sulfur above approximately 260°C (500°F).
Monel 400 vs Monel K500: Key Differences
Engineers frequently ask how Monel 400 Round Bar compares with Monel K500 Round Bar. The table below covers the critical selection criteria.
| Aspect | Monel 400 (UNS N04400) | Monel K500 (UNS N05500) |
|---|---|---|
| Composition | 63% Ni, 28–34% Cu | 63% Ni, 28–34% Cu + Al + Ti |
| Strengthening Method | Cold working only | Precipitation hardening (age-hardening) |
| Tensile Strength (annealed) | 550 MPa (80,000 psi) | Up to 1100 MPa (aged) |
| Yield Strength (annealed) | 240 MPa (35,000 psi) | 690–760 MPa (age-hardened) |
| Hardness | 110–149 HB (annealed) | B95 to C30 HRC |
| Weldability | Good — TIG, MIG, SMAW | Reduced — requires pre- and post-weld care |
| Magnetic | Slightly magnetic at ambient | Slightly magnetic |
| Governing Standard | ASTM B164 / ASME SB164 | ASTM B865 |
| Relative Cost | Lower | Approx. 20–30% higher |
| Best Applications | Marine, chemical, oil & gas, nuclear | Aerospace fasteners, pump shafts, springs |
See our detailed comparison: Monel 400 vs Monel K500 Round Bars.
ASTM B164 Monel 400 Round Bars Specifications
| Parameter | Details |
|---|---|
| Primary Standard | ASTM B164 / ASME SB164 |
| Aerospace Standard | AMS 4675 / AMS 4730 / AMS 4731 |
| Military / Federal Spec | QQ-N-281 |
| German Pressure Vessel | VdTUV 263 |
| UNS Number | N04400 |
| Werkstoff Number | 2.4360 |
| Round Bar Diameter | 3 mm to 800 mm |
| Flat Bar | Thickness: 2 mm to 100 mm | Width: 10 mm to 500 mm |
| Square Bar | 4 mm × 4 mm to 100 mm × 100 mm |
| Hex Bar | Up to 100 mm across flats |
| Hollow Bar | 32 mm OD × 16 mm ID to 250 mm OD × 200 mm ID |
| Billet Size | 1/2 inch to 495 mm diameter |
| Standard Length | 1,000 mm to 6,000 mm; custom cut lengths available |
| Dimensional Standards | EN, DIN, JIS, ASTM, BS, ASME, AISI |
| Density | 8.8 g/cm³ (0.318 lb/in³) |
| Melting Point | 1350°C (2460°F) |
| Hardness | 60–80 HB (hot rolled); 110–149 HB (annealed) |
| Annealing Temperature Range | 870°C to 980°C (1600°F to 2150°F) |
| Surface Finish | Black, Polished, Hairline, Pickled, Bright Drawn, Centreless Ground, TG&P, DG&P |
| Supply Conditions | Annealed, Cold Drawn, Precipitation Hardened, Hardened and Tempered |
| Manufacturing Technique | Hot Rolled, Cold Drawn, Forged, Centreless Ground |
Monel 400 Bar Chemical Composition
| Grade | Ni (min) | Cu | Fe | Mn | C | Si | S | Co (max) |
|---|---|---|---|---|---|---|---|---|
| Monel 400 | 63.0% | 28.0–34.0% | 1.0–2.5% | 2.0% max | 0.3% max | 0.5% max | 0.024% max | 0.50% |
Monel Alloy 400 Round Bars Mechanical Properties
| Condition | Tensile Strength | Yield Strength (0.2%) | Elongation | Hardness | Density | Melting Point |
|---|---|---|---|---|---|---|
| Annealed | 550 MPa / 80,000 psi | 240 MPa / 35,000 psi | 40% | 110–149 HB | 8.8 g/cm³ | 1350°C / 2460°F |
| Cold Drawn | 690 MPa / 100,000 psi | 517 MPa / 75,000 psi | 25% | Up to 200 HB | 8.8 g/cm³ | 1350°C / 2460°F |
| Cold Worked (max) | 760 MPa / 110,000 psi | 483 MPa / 70,000 psi | 35% | B60–B95 HRB | 8.8 g/cm³ | 1350°C / 2460°F |
Monel 400 Physical and Thermal Properties
The physical and thermal properties of Monel 400 Round Bar govern its suitability for heat exchanger design, cryogenic applications, and elevated-temperature process service. The values below are consistent with ASTM B164 / ASME SB164 specification requirements and published NIST / Special Metals data.
| Property | Value | Notes |
|---|---|---|
| Density | 8.8 g/cm³ (0.318 lb/in³) | Per ASTM B164 |
| Melting Range | 1300–1350°C (2370–2460°F) | Solidus–Liquidus |
| Modulus of Elasticity (E) | 179 GPa (26,000 ksi) | Used for shaft deflection calc. |
| Coefficient of Thermal Expansion | 13.9 µm/m·°C (at 21–100°C) | Increases with temperature |
| Thermal Conductivity | 21.8 W/m·K (at 21°C) | ~21–45 W/m·K across service range |
| Specific Heat Capacity | 427 J/kg·°C (at 21°C) | — |
| Electrical Resistivity | 0.511 µΩ·m (at 21°C) | — |
| Magnetic Permeability | Slightly magnetic at ambient temperature | Decreases as temperature rises |
Monel 400 Equivalent Standards and Grades
| Standard | Werkstoff Nr. | UNS | JIS | BS | GOST | AFNOR | EN / Military |
|---|---|---|---|---|---|---|---|
| Monel 400 | 2.4360 | N04400 | NW 4400 | NA 13 | MNZhMTs 28-2.5-1.5 | NU-30M | NiCu30Fe / QQ-N-281 |
Monel Alloy 400 Round Bar Tolerances
Tolerances per ASTM B164 / ASME SB164 unless otherwise specified. Custom tolerances available on request.
| Shape | Size Range | ISO Tolerance Class | Permitted Variation |
|---|---|---|---|
| Round Bar (Cold Drawn & Polished) | 3.0 – 75.0 mm (1/8″ – 3″) | h8 – h11 | Per ISO 286-1 |
| Round Bar (Cold Drawn & Ground) | 10.0 – 75.0 mm (5/16″ – 2.5″) | h8 – h11 | Per ISO 286-1 |
| Round Bar (Peeled & Polished) | 40.0 – 150.0 mm (1.5″ – 6″) | h11 (ASTM A484 / DIN 1013) | Per ASTM A484 |
| Round Bar (ASTM B164 standard) | Up to 25.4 mm (1″) | — | ± 0.016 inch |
| Round Bar (ASTM B164 standard) | Over 1″ to 2″ | — | +0.031″ / –0.016″ |
| Round Bar (ASTM B164 standard) | Over 2″ to 4″ | — | +0.047″ / –0.031″ |
| Round Bar (ASTM B164 standard) | Over 4″ | — | +0.125″ / –0.063″ |
| Flat Bar (thickness) | 2 mm – 100 mm | H8 to H13 / K9 to K12 | Per DIN 1017 |
| Hex Bar | Up to 100 mm A/F | H8 to H13 | Per ISO 286-1 |
Monel 400 Round Bar Weight Chart and Size Guide (kg/m)
Theoretical weights based on density 8.8 g/cm³ per ASTM B164. Actual weight may vary ± 2% depending on finish and tolerance class.
| Dia (mm) | kg/m | Dia (mm) | kg/m | Dia (mm) | kg/m | Dia (mm) | kg/m | Dia (mm) |
|---|---|---|---|---|---|---|---|---|
| 3 | 0.062 | 25 | 4.33 | 65 | 29.26 | 130 | 117.0 | 250 |
| 5 | 0.173 | 30 | 6.24 | 70 | 33.91 | 140 | 136.0 | 300 |
| 6 | 0.249 | 32 | 7.10 | 75 | 39.10 | 150 | 155.8 | 350 |
| 8 | 0.443 | 35 | 8.50 | 80 | 44.31 | 160 | 177.3 | 400 |
| 10 | 0.692 | 38 | 10.02 | 90 | 56.07 | 180 | 224.5 | 500 |
| 12 | 0.996 | 40 | 11.09 | 100 | 69.24 | 200 | 276.9 | 600 |
| 16 | 1.773 | 45 | 14.03 | 110 | 83.79 | 220 | 335.0 | 700 |
| 20 | 2.771 | 50 | 17.31 | 120 | 99.70 | — | — | 800 |
Use our Metal Weights Calculator for custom size weight estimates.
Monel 400 Round Bar Machinability, Fabrication and Welding
Machinability of Monel 400 Bar
Monel 400 bar stock machines most efficiently in the annealed condition. The alloy has a strong tendency to work-harden during cutting, which requires specific tooling and process discipline to avoid built-up edge and poor surface finish. Recommended machining practices:
- Use sharp, polished high-speed steel (HSS) or carbide tooling with positive rake angles
- Apply moderate, constant cutting speeds — approximately 60–90 m/min for turning; avoid dwelling
- Maintain continuous, even feed rates — interruptions promote work-hardening ahead of the tool
- Use generous flood coolant or cutting oil to manage heat and chip adhesion
- For precision-turned components (pump shafts, valve stems, bearing journals), specify centreless-ground or TG&P (turned, ground and polished) bar to achieve tight tolerance without heavy stock removal
The annealed condition is strongly preferred over cold-drawn material for precision boring and threading because its lower yield strength and higher ductility produce cleaner chip break. Cold-drawn Monel 400 bar is preferred where higher surface hardness and dimensional stability are needed for light-duty machining operations.
Forming and Fabrication
Monel 400 can be formed by hot or cold working. Hot working should be carried out in the range 870°C to 1180°C (1600°F to 2150°F) with forging completed above 870°C to avoid cracking. Cold working significantly increases tensile and yield strength — reanneal at 870°C to 980°C if ductility needs to be restored between forming operations.
Alloy 400 Round Bar Surface Finish Options
| Code | Description | Code | Description |
|---|---|---|---|
| No.1 | Hot Rolled, Annealed, Pickled | CD | Cold Drawn |
| 2B | Cold Rolled, Annealed, Skin-Passed | BA | Bright Annealed |
| No.4 | Brushed / Linished | Peeled | Rough Turned / Peeled |
| No.8 | Mirror Polished | TG&P | Turned, Ground and Polished |
| No.3 | Coarse Ground | DG&P | Drawn, Ground and Polished |
HS Code for Monel 400 Bar
| Grade | HS Code |
|---|---|
| Monel 400 (UNS N04400 / Werkstoff 2.4360) | 75051220 |
The HS code 75051220 applies to nickel alloy bars not further worked than hot-rolled, under WTO member country customs schedules. Jade Alloys includes the correct HS code on all commercial invoices and export documentation.
Applications of Monel 400 Round Bars
Marine Engineering
Monel 400 bar stock is specified for propeller shafts, pump shafts, valve stems, impeller shafts, and seawater piping where continuous immersion in brackish or saline water is unavoidable. Its extremely low corrosion rate in rapidly flowing seawater makes it suitable where 316L stainless steel cannot perform. Unlike austenitic stainless, alloy 400 bar does not pit or suffer stress-corrosion cracking in marine chloride environments. The alloy also resists microbially induced corrosion (MIC) — critical for offshore platform legs, underwater structures, and submerged pump systems.
Chemical Processing
Monel 400 round bar is used in heat exchangers, reaction vessels, agitators, and piping systems handling acids, alkalis, and chloride-bearing process streams. Its resistance to hydrochloric acid and hydrofluoric acid (when de-aerated) is particularly valued in pharmaceutical and specialty chemical production.
Oil and Gas
Alloy 400 round bar is specified for pump shafts, valve stems, wellhead components, and downhole tools in sour service environments. NACE MR0175 / ISO 15156 compliance is available on request.
Aerospace and Defence
AMS 4675, AMS 4730, and AMS 4731 specifications cover the Monel 400 bar for aerospace applications. The alloy is used in fuel and oxidiser systems, fasteners, and structural components where corrosion resistance and consistent mechanical properties are critical across wide temperature ranges. The QQ-N-281 federal specification applies to US defence procurement.
Nuclear and Uranium Processing
Monel 400 is one of the very few structural alloys resistant to uranium hexafluoride (UF6) and hydrofluoric acid simultaneously, making it the standard material for uranium enrichment plant components, gaseous diffusion barriers, and nuclear processing equipment. This is a niche but technically demanding application where alloy substitution is not possible.
Desalination and Water Treatment
Monel 400 round bars are machined into brine heater components, evaporator tube sheets, and pump shafts for multi-stage flash (MSF) and multi-effect distillation (MED) desalination plants. High-salinity brines at elevated temperatures cause rapid corrosion in copper alloys and carbon steel — alloy 400 bar provides decades of service life in these conditions.
Pulp and Paper
The alloy resists bleaching agents, chlorine compounds, and acidic process liquors in pulp and paper production. It is specified for digesters, bleach plant piping, brown stock washers, and drum-type filter equipment where stainless steel grades are inadequate against chlorine dioxide.
Pharmaceutical and Food Processing
Monel 400 is preferred in drug manufacturing and food-grade process equipment where chloride-induced stress-corrosion cracking of 316L stainless steel is a risk and where FDA-acceptable surface finishes are required.
Monel 400 Round Bar Price in India
Monel 400 Round Bar price in India fluctuates with London Metal Exchange (LME) nickel and copper spot rates, order quantity, diameter, surface condition (black / bright drawn / polished / centreless ground), and applicable export documentation requirements. As a direct manufacturer and exporter, Jade Alloys prices from mill rates with no intermediary markup. Contact us for a firm quotation with EN 10204 3.1 MTC within 24 hours.
| Diameter Range | Typical Condition | Ex-Works Availability | Lead Time |
|---|---|---|---|
| 10 mm – 40 mm | Annealed / Cold Drawn | Ex-Stock Mumbai | Same-week dispatch |
| 40 mm – 100 mm | Hot Rolled / Forged, Peeled | Ex-Stock Mumbai | Same-week dispatch |
| 100 mm – 300 mm | Forged, Annealed, Peeled | Ex-Stock / Short Lead | 3–5 working days |
| 300 mm – 800 mm | Forged, Annealed | Order-to-Mill | 10–15 working days |
Note: Indicative availability only. Prices are subject to change without notice. Actual ex-works price depends on LME rates at time of order. Contact sales@jadealloys.com or +91 9987685906 for a current price with MTC.
Does Heat Treatment Work for Monel 400 Bar?
| Point | Details |
|---|---|
| Standard Heat Treatment | Not required and not recommended as a strengthening method — Monel 400 is a solid-solution alloy. |
| Annealed Condition | Used to restore ductility and optimise corrosion resistance after cold working. Annealing temperature: 870°C–980°C. Best condition for welding, forming, and fabrication. |
| Cold Working | The only way to increase strength without alloying additions. Tensile strength increases from 550 MPa (annealed) to up to 760 MPa (heavily cold-worked). |
| Microstructure Caution | Heat treatment above the annealing range can degrade mechanical properties and promote grain growth. Avoid prolonged exposure above 980°C. |
| Post-Fabrication Annealing | Recommended for thick-section weldments or heavily cold-worked components that will see corrosive service. Consult a metallurgist for specific applications. |
Monel 400 Rod Welding Considerations
Pre-Weld Preparation
Ensure all joint surfaces are thoroughly clean and free of oil, grease, scale, sulfur compounds, and all other contaminants before welding. Sulfur is particularly damaging — even trace amounts from cutting oils or marking compounds can cause hot cracking in the heat-affected zone.
Recommended Welding Processes and Filler Metals
| Process | Filler Metal | Notes |
|---|---|---|
| GTAW (TIG) | ERNiCu-7 | Preferred for precision work, thin sections, and root passes |
| GMAW (MIG) | ERNiCu-7 | Suitable for thicker sections and higher deposition rate applications |
| SMAW (Stick) | ENiCu-7 (Monel Welding Electrode 190) | Acceptable for site work and repair welding |
Heat Input and Post-Weld Treatment
Control heat input to minimise distortion and reduce risk of hot cracking. Maintain low interpass temperatures (below 150°C / 300°F). After welding, clean welds thoroughly to remove any oxide contamination. For thick sections or heavily restrained joints, consider stress relief annealing at 870°C to reduce residual weld stresses. ASME Section IX governs WPS (Welding Procedure Specification) qualification for pressure equipment applications.
Frequently Asked Questions About Monel 400 Round Bars
Is Monel 400 the same as Alloy 400?
What is the price of Monel 400 Round Bar in India?
Is Monel 400 magnetic?
What standard governs Monel 400 Round Bars?
Does Monel 400 require heat treatment?
What is the difference between Monel 400 and Monel K500?
What sizes of Monel 400 Round Bar does Jade Alloys stock?
Can Monel 400 be used in hydrofluoric acid service?
What welding rod is used for Monel 400?
What is the HS code for Monel 400 Round Bar?
What is the density of Monel 400?
Monel 400 Export and Delivery
Jade Alloys exports Monel 400 Round Bar from Mumbai with full export documentation: Bill of Lading, EN 10204 3.1 Mill Test Certificate, Country of Origin Certificate, Packing List, and Copy of Invoice. Third-party inspection (SGS, Bureau Veritas, TUV) is available on request. Indicative sea freight transit times from Mumbai:
Why Choose Jade Alloys for Monel 400 Round Bars?
Jade Alloys has supplied certified nickel alloy products for over two decades, serving OEM procurement teams, EPC contractors, and MRO distributors across oil and gas, chemical, and marine sectors from our warehouse in Mumbai, India.
- EN 10204 3.1 Mill Test Certificate on Every Order: Each batch of Monel 400 round bar is fully traceable to the melt heat number. MTC documentation is issued at point of dispatch — no exceptions.
- NABL-Accredited Lab Testing: Chemical and mechanical tests are carried out in an NABL-accredited laboratory. Test reports are available alongside EN 10204 3.1 MTCs for critical applications.
- NACE MR0175 / ISO 15156 Compliance: Available on request for sour service oil and gas applications. We supply certified compliance documentation alongside MTC packages.
- No Minimum Order Quantity: We supply the exact quantity required — from 1 kg trial orders to multi-tonne project packages. No footage minimums.
- Same-Week Dispatch: Ready stock in Mumbai for standard sizes (10 mm to 800 mm). Express export documentation including Bill of Lading, Country of Origin Certificate, and Packing List prepared within 24 hours.
- Third-Party Inspection Available: SGS, Bureau Veritas, and TUV inspection available on request. We welcome customer-nominated inspectors at our Mumbai warehouse.
- Value-Added Services: Heat treatment and annealing, machining and centreless grinding to ± 0.1 mm, pickling, mirror polishing, rolling, and forging — all in-house or through qualified sub-contractors.
- Over 50 Countries Served: Active customers across the Middle East, Europe, Southeast Asia, and the Americas. Export-ready documentation for all major shipping destinations.
