Alloy 404,Monel 404,，EFORU

### **Alloy 404 / Monel® 404 (UNS N04404) - Technical Datasheet** --- #### **1. Overview** **Monel® 404** is a nickel-copper alloy specifically formulated for specialized electrical and electronic applications requiring precise thermal expansion characteristics and excellent brazing properties. This alloy exhibits low magnetic permeability and controlled thermal expansion, making it particularly suitable for applications involving glass-to-metal seals and electronic components where thermal compatibility and electrical performance are critical. --- #### **2. Chemical Composition (Weight %)** The composition is carefully balanced for optimal electronic applications. | Element | Content (%) | Role & Benefit | |---------|-------------|----------------| | **Nickel (Ni)** | 52.0 - 57.0 | Provides strength and controls thermal expansion | | **Copper (Cu)** | Balance | Principal element for electrical conductivity | | **Iron (Fe)** | 0.15 max | Minimized for optimal magnetic properties | | **Manganese (Mn)** | 0.05 - 0.50 | Controlled for deoxidation and workability | | **Aluminum (Al)** | 0.05 max | Controlled impurity | | **Silicon (Si)** | 0.10 max | Controlled for brazing compatibility | | **Carbon (C)** | 0.15 max | Controlled for optimal properties | | **Sulfur (S)** | 0.015 max | Tightly controlled impurity | | **Magnesium (Mg)** | 0.05 - 0.15 | Grain refinement and sulfur control | *Note: "Monel" is a registered trademark of Special Metals Corporation* --- #### **3. Physical Properties** The physical properties highlight its electrical and thermal characteristics. | Property | Value | |----------|-------| | **Density** | 8.91 g/cm³ (0.322 lb/in³) | | **Melting Point** | 1300-1350°C (2370-2460°F) | | **Specific Heat (20°C)** | 460 J/kg·K | | **Thermal Conductivity** | 25.2 W/m·K (at 20°C) | | **Mean Coefficient of Thermal Expansion** | 13.9 × 10⁻⁶/°C (20-300°C) | | **Electrical Resistivity** | 0.49 μΩ·m | | **Modulus of Elasticity** | 162 GPa (23.5 × 10⁶ psi) | | **Magnetic Permeability** | < 1.005 (Essentially non-magnetic) | | **Thermal EMF vs Copper** | Approximately 35 μV/°C | --- #### **4. Mechanical Properties** The alloy offers a balance of strength and fabricability. **Annealed Condition:** | Property | Value | |----------|-------| | **Tensile Strength** | 410-510 MPa (60-74 ksi) | | **Yield Strength (0.2% Offset)** | 170-240 MPa (25-35 ksi) | | **Elongation** | 35-45% | | **Hardness** | 70-85 HRB | | **Fatigue Strength** | 220 MPa (32 ksi) | **Cold Worked Condition:** | Property | Value | |----------|-------| | **Tensile Strength** | 580-720 MPa (84-104 ksi) | | **Yield Strength** | 510-650 MPa (74-94 ksi) | | **Elongation** | 12-20% | | **Hardness** | 90-100 HRB | --- #### **5. Product Applications** **Monel 404** serves in specialized electronic and electrical applications: - **Electronics & Electrical Components:** - Glass-to-metal seal components - Transistor and IC package leads - Electrical connector springs - Lead frames for electronic packages - **Communications Equipment:** - Waveguide components - Microwave tube parts - RF connector components - Electronic packaging applications - **Aerospace & Defense:** - Avionics components - Radar system parts - Military communications equipment - Satellite components - **Industrial Applications:** - Resistance welding electrodes - Electrical contacts - Thermocouple elements - Precision instrument components - **Specialized Applications:** - Hermetic seals for electronic packages - Cryogenic electrical components - Vacuum tube components - Precision springs for electronic devices --- #### **6. International Standards** The material conforms to various international specifications: | Standard | Specification | |----------|---------------| | **ASTM** | ASTM F96 - Electronic Grade Alloys
ASTM B164 - Nickel-Copper Alloy Rod, Bar, and Wire | | **UNS** | UNS N04404 | | **AMS** | AMS 4675, AMS 4676 | | **Military** | MIL-E-5272, MIL-P-27725 | | **ISO** | ISO 6208 - NiCu55 | | **EN** | EN 10095 - NW 4400 | --- #### **7. Special Characteristics** - **Glass Sealing Compatibility:** Excellent for matched glass-to-metal seals - **Low Magnetic Permeability:** Essentially non-magnetic in all conditions - **Brazing Performance:** Excellent compatibility with common brazing alloys - **Thermal Expansion:** Controlled to match various glass and ceramic materials - **Stability:** Maintains dimensional stability during thermal cycling --- #### **8. Fabrication Characteristics** - **Machining:** Good machinability with proper tool selection - **Forming:** Excellent cold working characteristics - **Welding:** Good weldability using GTAW and electron beam methods - **Brazing:** Excellent performance with silver-based brazing alloys - **Annealing:** 700-850°C (1290-1560°F) in controlled atmosphere - **Glass Sealing:** Requires specific surface preparation and cleaning --- #### **9. Electrical & Thermal Properties** - **Electrical Conductivity:** ~34% IACS - **Thermal Conductivity:** Moderate, suitable for electronic applications - **Thermal Expansion Match:** Compatible with certain borosilicate glasses - **Surface Properties:** Requires clean surface for optimal glass sealing - **Oxidation Resistance:** Good in controlled atmospheres --- #### **10. Summary** **Monel® 404 (UNS N04404)** represents a specialized nickel-copper alloy engineered specifically for electronic applications requiring precise thermal expansion control and excellent sealing characteristics. Its optimized composition provides the ideal combination of low magnetic permeability, controlled thermal expansion, and good electrical conductivity, making it particularly valuable for glass-to-metal seals, electronic packaging, and precision electrical components. The alloy's ability to maintain stable properties during thermal cycling and its compatibility with common brazing and sealing processes establish it as a preferred material for critical electronic applications. Governed by comprehensive standards including AMS 4675 and ASTM specifications, Monel 404 continues to be the material of choice for applications where reliable performance in electronic and communications equipment is essential.

Packing of Standard Packing: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 1723 gallon liquid totes Special package is available on request.