Kovar 4J29 Sealing Rod Precision Polished for Hermetic Feedthroughs
Kovar 4J29 Sealing Rod Precision Polished for Hermetic Feedthroughs
Iron-nickel-cobalt alloy 4J29 alloy is also called Kovar alloy. 4J29 has a linear expansion coefficient close to that of silicon boron hard glass at 20 ° C to 450 ° C, which can be matched with hard glass to achieve sealing firmly. It has a high Curie point and has good low temperature tissue stability.
4J29 is mainly used for the glass sealing of electric vacuum components such as launch tubes, oscillation tubes, ignition tubes, magnetrons, transistors, sealed plugs, relays, integrated circuits, chassis, housings, brackets, etc.
4J29 Kovar Chemical Composition(%)
| Grade | C | Si | Mn | P | S | Ni | Co | Fe | Cu | Cr | Mo |
| 4J29 | ≤0.03 | ≤0.3 | ≤0.5 | ≤0.02 | ≤0.02 | 28.5-29.5 | 16.8-17.8 | Balance | ≤0. 2 | ≤0. 2 | ≤0. 2 |
When the average linear expansion coefficient reaches the standard stipulated conditions, the content of nickel and cobalt is allowed to deviate from the range specified in the table. The contents of aluminum, magnesium, zirconium and titanium are each not more than 0.10%, and the total amount should not be more than 0.20%
4J29 Kovar Linear Expansion Coefficient:
| Temperature Range | 20~100℃ | 20~300℃ | 20~400℃ | 20~450℃ | 20~500℃ | 20~600℃ | 20~700℃ |
| Average Linear Expansion Coefficient (10-6) |
5.8 |
5.3 |
4.6-5.2 |
5.1-5.5 |
6.2 |
7.8 |
9.2 |
4J29 Kovar Physical Properties:
| Density | 8.17g/cm3 |
| Curie Temp | 435℃ |
| Melting Point | 1449℃ |
| Thermal Conductivity | 0.17 W/cm °C |
| Tensile Strength | >518 MPa |
| Elongation | >30% |
| Hardness | >80HRB |
| Modulus of Elasticity | 30 Mpsi |
Supply Sate:
1. Sheet and foil (within a width of 2 meters)
Delivery status: hot rolled or cold rolled, annealed, pickled
2. Round plates and rings
Delivery status: hot rolled or cold rolled, annealed, pickled or machined
3. Wire
Delivery status: bright brushed, Hard, 1 / 4Hard, 1 / 2Hard, Soft
Specification: φ0.01-15mm, coiled, wrapped around a shaft or in roll form
4. Bar
Supply status: forged material, hot rolled material, cold drawn material, annealed state, pickled, machined or polished.
5. Forging
Delivery status: irregularly shaped forgings are provided upon request
6. Strip material (within 650mm, commonly used are 100mm, 150mm, 200mm, 300mm, 350mm)
Delivery status: 0.01mm-5.0mm, cold rolled, annealed, pickled or bright annealed
7. Flat wire, strip
4J29 Other Names Called International:
29HК / Kovar / Nilo K / KV-1 / Dilver P0 / Vacon 12 / 29HК-BИ / Rodar KV-2 / Techallony Glasseal 29-17 / Telcaseal KV-3 Dilver P1 / Silvar 48
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