kovar precision 4J29 plate
Kovar alloy is a vacuum melted, iron-nickel-cobalt alloy that is widely used in the electronics industry. Kovar is a nickel-iron-cobalt, controlled-expansion alloy which contains 29% nickel. Its coefficient of expansion, which decreases with rising temperature to the inflection point, matches the expansion rate of borosilicate glasses and alumina ceramics.
Kovar alloy has been used for making hermetic seals with the harder Pyrex glasses and ceramic materials. This alloy has found wide application in power tubes, microwave tubes, transistors, and diodes. In integrated circuits, it has been used for the flat pack and the dual-in-line package.
kovar precision 4J29 Chemical Composition:
| Grade | C | Mn | Si | P | S | Cr | Co | Ni | Fe | |
| Kovar |
Min | - | - | - | - | - | - | 16.8 | 28.5 | |
| max | 0.03 | 0.50 | 0.30 | 0.020 | 0.020 | 0.20 | 17.8 | 29.5 | bal |
Mechanical Properties
| Density | 8.17 g/cm3 |
| Melting Point | 1449°C |
Kovar Equivalent Grades:
| Grade | WERKSTOFF NR. |
UNS |
| Kovar | 1.3981 | K94610 |
