4J33 Rod Controlled Expansion Alloy Bar Fe Ni Co Alloy Precision Material
Product Description
4J33 alloy rod is a Fe-Ni-Co controlled expansion alloy containing about 33% nickel and cobalt. It is specially developed for applications requiring stable thermal expansion to match materials such as ceramics or glass.
This alloy combines good mechanical properties, excellent machinability, and stable expansion behavior, making it widely used in electronic packaging, vacuum devices, and precision instruments.
Key Features
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Fe-Ni-Co controlled expansion alloy
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Stable thermal expansion coefficient
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Excellent hermetic sealing performance with glass/ceramic
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Good processability and weldability
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Available in rods, wires, sheets, and customized forms
Typical Applications
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Electronic packaging and sealing
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Glass-to-metal and ceramic-to-metal seals
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Precision electronic components
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Vacuum tubes and relay parts
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Aerospace and instrumentation industry
Chemical Composition (%)
| Element | Content |
|---|---|
| Fe | Balance |
| Ni | ~33% |
| Co | ~17% |
| Mn, Si, C, etc. | Minor |
Physical and Performance Properties
| Property | Typical Value |
|---|---|
| Density | ~8.2 g/cm³ |
| Thermal Expansion (20–300°C) | ~5.0 ×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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