4J32 Alloy Tube (Invar 32-5 / Fe-Ni-Co Low Expansion Alloy Tube)
Product Overview
4J32 alloy tube, also known as Invar 32-5 or Fe-Ni-Co low-expansion alloy, is a precision tube material designed for applications requiring extremely stable dimensions under temperature variations.
With a thermal expansion coefficient similar to glass and ceramics, 4J32 tubing is widely used in optical instruments, aerospace components, precision measurement devices, vacuum systems, and electronic equipment.
It provides excellent processability, stable mechanical properties, and strong dimensional reliability.
Key Features
-
Ultra-Low Thermal Expansion
CTE ~3.5–4.0 ×10⁻⁶/°C (20–200°C). -
High Dimensional Stability
Maintains geometry under thermal cycling. -
Good Mechanical Strength
Suitable for structural and functional components. -
Excellent Weldability & Formability
Supports machining, drawing, welding, and fine fabrication. -
High Vacuum Compatibility
Low outgassing, suitable for aerospace and optics. -
Customizable Dimensions
OD / ID / wall thickness / length can be fully customized.
Technical Specifications
| Item | Value |
|---|---|
| Material | 4J32 (Fe-Ni-Co Low Expansion Alloy) |
| Equivalent Grade | Invar 32-5 |
| Ni Content | ~32% |
| Co Content | 4.5%–5.5% |
| Outer Diameter (OD) | 0.5–60 mm (custom available) |
| Wall Thickness | ≥ 0.5 mm |
| Inner Diameter (ID) | Custom |
| Length | 10–6000 mm (cut-to-length) |
| Surface Finish | Bright / Polished / Clean |
| Density | 8.2 g/cm³ |
| Melting Point | 1420–1450 °C |
| Thermal Expansion (20–200°C) | 3.5–4.0 ×10⁻⁶/°C |
| Hardness Condition | Annealed / Semi-hard / Hard |
| Tensile Strength | 500–650 MPa |
| Yield Strength | 300–400 MPa |
| Standards | GB/T 15009 |
Main Applications
| Industry | Uses |
|---|---|
| Aerospace | Sensor housings, support tubes, precision brackets |
| Optical Instruments | Lens frames, calibration tubes |
| Precision Measurement | Gauge tubes, dimensional stability components |
| Vacuum Systems | Vacuum fittings, cryogenic assemblies |
| Electronics | Relay parts, semiconductor supports |
| Automotive Sensors | Stability components, signal tubes |
Product Attributes(Alibaba Format)
| Attribute | Value |
|---|---|
| Material Grade | 4J32 / Invar 32-5 |
| Type | Low Expansion Alloy Tube |
| Composition | Fe-Ni-Co (Ni ~32%, Co ~5%) |
| Key Property | Ultra-Low Thermal Expansion |
| OD Range | 0.5–60 mm (custom) |
| Wall Thickness | ≥ 0.5 mm |
| Length | 10–6000 mm |
| Surface | Bright / Polished / Clean |
| Manufacturing Method | Seamless / Welded |
| Hardness | Annealed / 1/2 Hard / Hard |
| Density | 8.2 g/cm³ |
| Tensile Strength | 500–650 MPa |
| Yield Strength | 300–400 MPa |
| Application Field | Aerospace / Optical / Electronics / Measurement |
| Color | Metallic Grey |
| Form | Straight Tube / Coil / Cut Length |
| Customization | OD / ID / Length / Tolerance |
Get in Touch
Have questions about our products or want to discuss a custom order? Our team is ready to help you.