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4j29 Ni29co17 Kovar WIRE Precision Alloy Invar36 4j42 Iron Nickel Constant Expansion WIRE

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xModel NO. | Expansion Alloy | HS Code | 7505220000 |
---|---|---|---|
Purity | Alloy | Specification | Customized |
Origin | Jiangsu, China | Production Capacity | 1500tons/Year |
Highlight | 4j29 Low Expansion Alloy,4j29 iron nickel wire,ISO9001 Low Expansion Alloy |
Product Introduction – 4J29 Alloy Wire Rod (Kovar Equivalent)
4J29, also known as Kovar in international standards, is a Nickel–Iron–Cobalt controlled expansion alloy engineered for glass-to-metal and ceramic-to-metal sealing. Its thermal expansion closely matches that of hard glass and alumina ceramics, making it an ideal material for hermetic packaging, vacuum electronics, and aerospace components.
As a wire rod, 4J29 is supplied in spooled wire, straight rods, or custom-cut lengths, with tight dimensional tolerances and excellent surface finish.
Technical Specifications:
Property | Value |
---|---|
Alloy Name | 4J29 (Equivalent to Kovar) |
Chemical Composition | Ni: ~29%, Co: ~17%, Fe: Balance |
CTE (30–300°C) | ~5.0 × 10⁻⁶ /°C |
Density | ~8.3 g/cm³ |
Tensile Strength | 450–750 MPa (annealed) |
Yield Strength | ≥ 300 MPa |
Elongation | ≥ 25% |
Electrical Resistivity | ~0.42 μΩ·m |
Thermal Conductivity | ~17 W/m·K |
Melting Range | ~1450–1500°C |
Wire Rod Diameter Range | 0.1 mm – 6.0 mm (custom sizes available) |
Condition | Annealed / Bright / Oxidized / Pickled |
Packaging | Coils, straight rods, spool, or custom-cut |
Industry | Application Examples |
---|---|
Electronics | Transistor cans, relay headers, integrated circuit housings |
Optoelectronics | TO headers, photodiode cases, laser housings |
Aerospace | Hermetic sensors, thermal control components |
Vacuum Electronics | Tube components, getter assemblies |
Medical Devices | Sealed implantable components, bio-safe hermetic packaging |
Telecom | Fiber optic connectors, microwave & RF sealing elements |
Defense | Hermetically sealed sensors and modules |
Product Overview – 4J42 Alloy (Low Expansion Alloy)
4J42 is a Nickel-Iron alloy designed to have a low coefficient of thermal expansion (CTE). It is primarily used in applications that require precise dimensional stability across temperature variations, making it ideal for glass-to-metal sealing, ceramic-to-metal sealing, and high-precision electronic components.
This alloy is typically used in industries such as aerospace, electronics, and telecommunications, where the thermal expansion properties of materials are critical to maintaining the functionality and reliability of components.
Precision alloys are metal materials with special physical properties (such as magnetic, electrical, thermal and other properties). The vast majority of precision alloys are based on ferrous metals, and only a few are based on non-ferrous metals. Usually include magnetic alloys (see magnetic materials), elastic alloys, expansion alloys, thermal bimetals, electrical alloys, hydrogen storage alloys (see hydrogen storage materials), shape memory alloys, magnetostrictive alloys (see magnetostrictive materials), etc.
Industry | Application Examples |
---|---|
Electronics | Glass-to-metal seals for vacuum tubes, transistor cans, semiconductor housings |
Aerospace | Seals for sensors, connectors, and components in aerospace systems |
Telecommunications | Microwave and RF components, fiber optic connectors, satellite components |
Medical Devices | Hermetic sealing for implantable devices and bio-compatible sensors |
Automotive | Automotive electronic sensor housings, connectors, and precision seals |
Vacuum Systems | Vacuum tube components, electrical contacts |
Property | Value |
---|
Alloy Name | 4J42 (Nickel-Iron Alloy) |
Chemical Composition | Ni: ~42%, Fe: Balance |
CTE (20–100°C) | ~4.7 × 10⁻⁶ /°C |
Density | ~8.2 g/cm³ |
Tensile Strength | 450–700 MPa (annealed) |
Yield Strength | ≥ 300 MPa |
Elongation | ≥ 20% |
Hardness | ~160 HV (annealed) |
Electrical Resistivity | ~0.48 μΩ·m |
Magnetic Properties | Magnetic at room temperature |
Melting Range | ~1450°C |
Wire Diameter Range | 0.10 mm – 6.0 mm (custom sizes available) |
Surface Finish | Bright / Annealed / Oxidized |
Packaging | Spools, coils, or custom lengths |