Invar 36, also known as FeNi36 or Alloy 36, is a famous low thermal expansion nickel-iron alloy.
Invar 36 wire is widely trusted for precision projects that require stable size under temperature changes. This article shares what Invar 36 is and its core industrial uses.
Many standard alloy wires expand and deform easily with temperature shifts, causing precision equipment failure and inaccurate final data readings.
1. What Is Invar 36 Wire?
1.1 Basic Introduction
Invar 36 wire is a precision iron-nickel alloy wire containing 36% nickel.
It features an extremely low coefficient of thermal expansion at normal temperatures.
1.2 Core Material Trait
It hardly expands or shrinks with temperature rise or drop.
This unique property makes it irreplaceable for high-precision dimensional stability work.
2. Main Performance Advantages of Invar 36 Wire
2.1 Ultra-Low Thermal Expansion
Its expansion rate is only one-tenth of ordinary carbon steel.
Dimensions stay stable from cryogenic temperature up to 260°C working range.
No sudden dimensional fluctuation occurs even during repeated heating and cooling cycles in actual working conditions.
2.2 Good Mechanical & Processing Performance
Invar 36 wire has good ductility and tensile strength.
Easy to draw, bend, weld and process into various precision structural parts.
It does not crack or deform during fine wire drawing, perfect for ultra-thin customized wire production demands.
2.3 Reliable Long-Term Stability
No obvious deformation or aging after long-term service.
Perfect for equipment requiring consistent accuracy year after year.
It resists material fatigue and structural relaxation during long-term continuous industrial operation.
3. Invar 36 vs Ordinary Alloy Wire Comparison Table
The table below shows why Invar 36 wire is chosen for precision scenarios:
| Parameter | Invar 36 Wire | Ordinary Iron Steel Wire | Copper Nickel Wire |
| Thermal Expansion Level | Extremely Low | Very High | Medium |
| Dimensional Stability | Excellent | Poor | Good |
| Best Use Focus | Precision & temperature-sensitive parts | General structural use only | Corrosion & conductivity needs |
| Service Accuracy | High precision guaranteed | Easy to deform | Medium precision |
4. What Is Invar 36 Wire Used For? Core Application Fields
4.1 Precision Measurement & Scientific Instruments
Used for sensor leads, gauge components and measuring scale supports.
Prevents measurement errors caused by ambient temperature changes.
Ensures every test data remains accurate and repeatable for laboratory and industrial detection equipment.
4.2 Aerospace & Satellite Equipment
Applied for satellite structural wires and aerospace precision supports.
Keeps parts stable under extreme high and low temperature cycles.
Effectively avoids structural loosening and performance failure in harsh space working environments.
4.3 Optical & Laser Devices
Ideal for optical mounts, laser positioning frames and lens supporting wires.
Avoids optical deviation due to thermal expansion and contraction.
4.4 Electronics & Semiconductor Industry
Used for shadow mask frames and precision electronic connecting wires.
Ensures stable assembly size for semiconductor and display components.
4.5 Cryogenic & Liquefied Gas Equipment
Suitable for low-temperature pipeline accessories and cryogenic device wiring.
Maintains stable performance in ultra-low temperature working environments.
5. Our High-Quality Invar 36 Wire Products
5.1 Complete Specifications
We supply standard Invar 36 (4J36, UNS K93601) wire in full diameter ranges.
Available from ultra-fine 0.05mm to 5.0mm for different precision needs.
All wire sizes are strictly controlled with tight diameter tolerance for high-precision assembly matching.
5.2 Customized Processing
Custom wire tolerance, surface treatment and cut-to-length service available.
Supports small-batch sample orders and large-scale bulk production.
5.3 Strict Quality Control
Every batch is tested for thermal expansion coefficient and size tolerance.
All products comply with international ASTM and EN industrial standards.
Each order is fully inspected before shipment to guarantee stable and reliable batch consistency.
6. Conclusion
Invar 36 wire is mainly used for all scenarios requiring ultra-stable dimensions under temperature change.
It covers precision instruments, aerospace, optics, electronics and cryogenic industries.
If you need reliable and high-precision Invar 36 wire for your project, contact us for professional support and fast quotation.
Post time: Apr-27-2026
