4J36 Rod Invar Alloy Bar Fe Ni Alloy Controlled Expansion Material
Product Description
4J36 alloy rod, also known as Invar 36, is a low expansion Fe-Ni alloy containing about 36% nickel. It is widely recognized for its extremely low coefficient of thermal expansion (CTE) around room temperature.
This property makes 4J36 ideal for applications requiring dimensional stability under temperature fluctuations, such as precision instruments, measuring devices, aerospace, and cryogenic engineering.
Key Features
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Fe-Ni controlled expansion alloy (Ni ~36%)
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Very low thermal expansion coefficient
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Excellent dimensional stability
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Good machinability and weldability
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Available in rods, wires, sheets, and custom forms
Typical Applications
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Precision measuring instruments
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Optical and laser system components
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Aerospace and satellite structures
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Electronic packaging requiring dimensional stability
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Cryogenic engineering devices
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Standards of length, balance springs, precision pendulums
Chemical Composition (%)
| Element | Content |
|---|---|
| Fe | Balance |
| Ni | ~36% |
| C, Mn, Si, etc. | Minor |
Physical and Performance Properties
| Property | Typical Value |
|---|---|
| Density | ~8.1 g/cm³ |
| Thermal Expansion (20–100°C) | ~1.2 ×10⁻⁶/°C |
| Tensile Strength | ≥ 450 MPa |
| Hardness | ~HB 120–150 |
| Working Temp | -200°C to 200°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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