4J42 Rod Controlled Expansion Alloy Bar Fe Ni Precision Alloy Material
Product Description
4J42 alloy rod is a Fe-Ni controlled expansion alloy containing about 42% nickel. It features a linear thermal expansion coefficient closely matching that of hard glass and ceramics, making it ideal for glass-to-metal and ceramic-to-metal sealing applications.
This alloy offers stable expansion performance, good processing properties, and excellent sealing reliability, widely used in electronic packaging, vacuum devices, and aerospace components.
Key Features
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Fe-Ni controlled expansion alloy
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Stable thermal expansion coefficient
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Excellent sealing performance with glass/ceramic
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Good machinability and weldability
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Supplied in rods, wires, strips, and customized forms
Typical Applications
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Glass-to-metal and ceramic-to-metal seals
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Electronic packaging housings
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Vacuum tubes, relays, and electronic devices
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Semiconductor device supports
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Aerospace and precision instruments
Chemical Composition (%)
| Element | Content |
|---|---|
| Fe | Balance |
| Ni | ~42% |
| Mn, Si, C, etc. | Minor |
Physical and Performance Properties
| Property | Typical Value |
|---|---|
| Density | ~8.1 g/cm³ |
| Thermal Expansion (20–300°C) | ~5.3 ×10⁻⁶/°C |
| Tensile Strength | ≥ 450 MPa |
| Hardness | ~HB 130–160 |
| Working Temp | -60°C to 400°C |
| Standard | GB/T, ASTM, IEC |
Available Specifications
| Item | Range |
|---|---|
| Diameter | 3 mm – 200 mm |
| Length | ≤ 6000 mm |
| Tolerance | As per ASTM / GB standard |
| Surface | Bright / Polished / Black |
| Packaging | Wooden case, steel strip bundling |
| Certification | ISO 9001, SGS, RoHS |
| Origin | China (OEM/ODM service available) |
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