An alloy engineered to expand at nearly the same rate as glass and ceramic, enabling reliable glass-to-metal seals.
An alloy engineered to expand at nearly the same rate as glass and ceramic, so metal and glass can be bonded without cracking as temperature changes.
Matched thermal expansion to hard glass and ceramics — its entire purpose is enabling a reliable glass-to-metal seal.
Only where a hermetic glass-to-metal or ceramic-to-metal seal is actually needed — a narrow, specific use case.
Hermetic seals, vacuum tube components, electronic package lids, microwave equipment housings.
Requires sharp carbide tooling and consistent coolant flow — similar machining character to other nickel-based alloys. Seal pins and glass-to-metal feedthrough bodies in Kovar are normally CNC turned, with seal faces finished by precision grinding. Kovar’s low expansion and its glass-sealing behaviour are also why it appears in semiconductor equipment components and in vacuum and electronic hardware more generally.
| Density | 8.3-8.4 g/cm3 |
| Typical Hardness | Rockwell B78-B82 |
| Typical Strength | 50,000-60,000 PSI yield |
| Lead Time | Confirmed per RFQ |
| Finishing | Confirmed per RFQ |
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