Custom Kovar Alloy Parts

Kovar’s thermal expansion coefficient (5.1 × 10⁻⁶ /°C) closely matches borosilicate glass and alumina ceramics. This matching prevents thermal stress and cracking during temperature changes, ensuring reliable hermetic seals for electronic packages, vacuum tubes, and sensors requiring atmospheric protection.

Yes, Kovar can be welded using TIG, resistance, or laser welding with proper procedures. It’s also commonly brazed to glass, ceramics, or other metals using gold, silver, or copper-based brazing alloys. Proper cleaning and oxidation control are critical for strong, hermetic joints.

Our precision CNC machining capabilities allow tolerances as tight as ±0.01mm for critical Kovar components. We use specialized tooling and cutting parameters optimized for this nickel-cobalt-iron alloy, with CMM inspection to verify dimensions for hermetic sealing applications.

Yes, we offer various surface treatments including gold plating for wire bonding and corrosion resistance, nickel plating for improved solderability, and controlled oxidation for glass sealing. We can also provide cleaning and passivation treatments for critical hermetic applications.

While both are low-expansion alloys, Kovar (29Ni-17Co-Fe) matches glass expansion and is used for glass sealing. Invar (36Ni-Fe) has near-zero expansion and is used for dimensional stability applications. Kovar is preferred for electronic packages while Invar suits precision instruments and tooling.

Yes, we provide comprehensive material traceability including mill certificates with chemical composition analysis verifying Fe-Ni-Co content, thermal expansion coefficient test data, mechanical property reports, and dimensional inspection documentation. All materials meet ASTM F15 specifications.