4J42 Glass-Sealing Alloy Specification
Fe-Ni Alloy for Precision Glass-to-Metal Sealing Applications
Product Specification
| Standard | GB/T 15018 (China), ASTM F15 (USA) |
| Material Designation | 4J42 (Fe-Ni), Ni42 Alloy |
| Tolerance | h7-h11 (on request) |
| Melt Method | Vacuum Induction Melting (VIM) |
| Available Forms & Sizes | Strip: 0.05-3.0mm thick (≤300mm width) Wire: φ0.10mm – φ5.0mm Bar: 3-100mm diameter Sheet: 35mm-151mm thickness |
Chemical Composition (wt%)
| Element | Min | Max |
| Nickel (Ni) | 41.5 | 42.5 |
| Iron (Fe) | Balance | |
| Manganese (Mn) | – | 0.50 |
| Silicon (Si) | – | 0.30 |
| Carbon (C) | – | 0.05 |
| Copper (Cu) | 0.10 | 0.25 |
| Phosphorus (P) | – | 0.02 |
| Sulfur (S) | – | 0.02 |
Thermal & Physical Properties
| Property | Value | Test Condition |
| Average CTE (20-300°C) | 6.5-7.5 ×10⁻⁶/°C | Annealed condition |
| Average CTE (20-400°C) | 7.8-8.8 ×10⁻⁶/°C | Annealed condition |
| Density | 8.1 g/cm³ | Room temperature |
| Melting Point | 1420-1450°C | |
| Curie Temperature | 360-390°C | |
| Thermal Conductivity | 16.8 W/(m·K) | 20°C |
| Electrical Resistivity | 0.45 μΩ·m | 20°C |
Mechanical Properties
- Tensile Strength: 480-550 MPa
- Yield Strength (0.2%): 320-400 MPa
- Elongation: ≥35%
- Hardness: 130-170 HV
- Modulus of Elasticity: 140 GPa
- Fatigue Strength: 200-260 MPa
- Poisson’s Ratio: 0.30
- Magnetic Permeability: 1.003-1.005
Applications
- Aerospace electronic housings and connectors
- Semiconductor packaging and chip carriers
- Lighting component bases and seals
- Laboratory instrument seals and connectors
- Medical device hermetic seals
- Electronic component housings
Special Processing Notes
- Recommended heat treatment: 850°C±10°C water quench for optimal CTE
- Hydrogen firing at 950-1050°C for 15-30 minutes required for glass sealing applications
- Avoid nickel plating before glass sealing operations
- Store in dry, controlled environment (≤40% RH) to prevent surface oxidation
Document generated on 2026/2/2 | For reference purposes only
