High Precision 4J32 Alloy Wire Low Expansion Fe-Ni Wire For Vacuum And Sensor Applications
Product Overview
4J32 alloy wire is a precision nickel-iron alloy with a low and controlled coefficient of thermal expansion, specifically designed for glass-to-metal sealing applications. With approximately 32% nickel, this alloy provides excellent compatibility with hard glass and borosilicate glass, ensuring reliable hermetic sealing in electronic vacuum devices, sensors, and military-grade packages.
Material Composition
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Nickel (Ni): ~32%
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Iron (Fe): Balance
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Minor elements: Manganese, Silicon, Carbon, etc.
Thermal Expansion (30–300°C): ~5.5 × 10⁻⁶ /°C
Density: ~8.2 g/cm³
Tensile Strength: ≥ 450 MPa
Resistivity: ~0.45 μΩ·m
Magnetic Properties: Soft magnetic behavior with stable performance
Available Sizes & Supply
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Diameter: 0.02 mm – 3.0 mm
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Length: in coils, spools, or cut-to-length as required
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Condition: Annealed or cold drawn
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Surface: Bright, oxide-free, smooth finish
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Packaging: Vacuum-sealed bags, anti-rust foil, plastic spools
Key Features
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Excellent match with glass for hermetic sealing
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Stable low thermal expansion performance
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High purity and clean surface for vacuum compatibility
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Easy to weld, shape, and seal under various processes
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Customizable size and packaging options for different applications
Applications
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Glass-to-metal sealed relays and vacuum tubes
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Sealed electronic packages for aerospace and defense
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Sensor components and IR detector housings
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Semiconductor and optoelectronic packaging
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Medical devices and high-reliability modules
Get in Touch
Have questions about our products or want to discuss a custom order? Our team is ready to help you.



