We introduce machining examples of pure nickel and nickel alloys
Pure nickel exhibits excellent corrosion resistance to caustic soda and chlorine gas. Pure nickel has a melting point of 1433°C and offers good heat resistance
Invar is an alloy composed of 36% nickel and 64% iron. It has near-zero thermal expansion at room temperature. The name Invar comes from “invariable steel,” meaning non-deforming steel. Super Invar, which has even lower thermal expansion than Invar, is also available.
Kovar is an alloy composed of 29% nickel, 17% cobalt, and 54% iron. It has a low thermal expansion coefficient close to hard glass and is mainly used for glass sealing applications. It is also used for ceramic sealing, electronic tubes, and electronic components as a bonding material
Nickel Alloys (Ni)
Corrosion Resistance · Heat Resistance
Compatible with Diffusion Bonding
Typical properties of pure nickel and nickel alloys
| Item | Purity (%) |
Bulk Density (g/㎤) |
Vickers Hardness (GPa) |
Young’s Modulus (GPa) |
Melting Point (℃) |
Coefficient of Thermal Expansion (10-⁶/℃) |
Thermal Conductivity (W/(m·K)) |
Volume Resistivity (Ω･㎝) |
|---|---|---|---|---|---|---|---|---|
| Material | ||||||||
| Ni | 99.0 | 8.88 | 0.638 | 200 | 1433 | 12.9 (RT) |
72.7 | 9.2×10-⁶ |
| Invar | Ni 36% Fe 64% |
8.12 | 168 | 140–150 | 1426 | 1.2~2.0 | 13 | 75~85 ×10-⁶ |
| Kovar | Ni 29% Fe 54% Co 17% |
8.0–8.3 | 1.5–1.6 | 159 | 1,450 | 5.2～6.2 (RT) |
17 (20℃) |
49×10-⁶ (20℃) |
Applications Utilizing Material Properties
| Item | Features | Applications |
|---|---|---|
| Corrosion Resistance | · Pure nickel has high corrosion resistance to alkali and nitrogen gas | · Materials for caustic soda production equipment |
| Magnetic Properties | · Pure nickel has very high magnetic permeability | · Electromagnetic shielding materials · Transducers |
| Low Thermal Expansion | · Invar has near-zero thermal expansion at room temperature | · Clock pendulums · LNG tanks and pipes · CRT Shadow Mask |
| Kovar has thermal expansion close to hard glass | · Sealing with glass · Sealing with ceramics · Optical communication related · Vacuum tube related |
Machinable Sizes
| Item | Sizes (mm) | Item | Sizes (mm) |
|---|---|---|---|
| Plate Dimensions | 500 × 800 × 30 | Hole Diameter | Φ0.03– |
| Rod Dimensions | Φ100 ×500 | Hole Depth | –300 |
| Grooves | Width 0.1– | Number of Holes | –10,000 |
| Step | –100 | Threads | M1.2– |
