4J36 Invar Wire for Thermostatic Applications | Fe-Ni Alloy Wire with Controlled Thermal Expansion

Product Overview

4J36 alloy wire, commonly known as Invar 36 wire, is a precision Fe-Ni alloy with an extremely low coefficient of thermal expansion (CTE). It contains approximately 36% nickel and is widely used in applications requiring dimensional stability across temperature changes, such as precision instruments, aerospace components, and electronic devices.

Material Composition

• Nickel (Ni): ~36%

• Iron (Fe): Balance

• Others: Trace amounts of Mn, Si, C, etc.

Thermal Expansion (20–100°C): ~1.0–1.5 × 10⁻⁶ /°C
Density: ~8.1 g/cm³
Resistivity: ~0.78 μΩ·m
Tensile Strength: ≥ 450 MPa
Magnetic Properties: Soft magnetic, stable under thermal cycling

Available Sizes

• Diameter: 0.02 mm – 3.0 mm

• Length: coil, spool, or cut-to-length as needed

• Surface: Bright, smooth, oxide-free

• Condition: Annealed or cold drawn

• Custom dimensions accepted

Key Features

• Extremely low thermal expansion

• Excellent dimensional stability

• Easy to weld and process

• High purity and oxidation resistance

• Vacuum compatible for sealed applications

• Custom packaging available

Applications

• Aerospace and satellite components

• Bimetallic thermostats and precision instruments

• Optical mounts and sensor elements

• Electronic device sealing and packaging

• Laser and infrared systems

• Measuring tools and calibration equipment

Packaging & Shipping

• Vacuum packaging, spools, or anti-rust film

• Air, sea, or express delivery available

• Lead time: 7–15 working days

Huona (Shanghai) New Material Co., Ltd. Was established in 2008, currently have three divisions: Magnesium Division, Thermal Spray Division and Functional Material Division.

Magnesium Division produces magnesium metal products. Various models of high-quality magnesium alloy plate, magnesium rods, high-purity magnesium, magnesium plate, magnesium die casting, magnesium extrusion profiles and other metal magnesium and deep processing products.

Thermal spray wire Division offers a wide variety of pure metal and metal alloy wires, including nickel-, iron-, aluminum-, and zinc-based wires for thermal spray projects.

Fuctional Material Division supply electronic packaging COMPONENTS(GTMS, CTMS), soft magnetic alloys and bimetal strip.

Our company is certified by ISO9001 quality system and ISO14001 environmental protection system.

Mission Statement

We try our best to understand and utilize information within the environment. With this competency, we assist customers to create added value and contribute to the development of industry and healthy living.

We strive for "Best, " welcome challenges, and are relentless till we deliver products and solutions.