Kovar / Nilo K / Alloy K (UNS K94610 )
Kovar (Nilo K / Alloy K / UNS K94610) is an iron-nickel-cobalt controlled-expansion alloy engineered so that its coefficient of thermal expansion (CTE ≈ 5.5 × 10⁻⁶ / °C over 30–400 °C) closely matches that of borosilicate glass and alumina ceramics. This precise match allows metal and glass/ceramic to be joined into stress-free, hermetically sealed assemblies that survive repeated thermal cycling without cracking.
Kovar is the global industry standard for glass-to-metal and ceramic-to-metal seals — specified in hermetic electronic packages, semiconductor housings, vacuum feedthroughs, aerospace connectors, laser diode packages, RF/microwave enclosures, and X-ray tubes. Available in strip, sheet, bar, wire, tube, and deep-drawn or machined components (pins, leads, frames, lids, housings).
- CTE Precisely Matched to Borosilicate Glass & Alumina Ceramics
- The Hermetic Packaging Industry Standard
- Stable Expansion Behavior from Cryogenic to 400 °C+
- Excellent Formability for Complex Component Geometries
- Decades of Proven Reliability in Critical Applications
Product Specifications
4J29
strength
strength
hardness
Real Factory, Real Quality
- Proven Equipment: Our machinery is well-maintained and fine-tuned over years for stable production.
- Rigorous Quality Control: Each item is manually inspected before shipment — no shortcuts.
- Honest Timeline: We don’t claim “instant delivery”, but we guarantee “on-time, as promised”.
- Flexible Customization: Small orders welcome. We adapt to your specific needs.
- 100% Real Footage: The video on the right is our actual workshop — what you see is what you get.
Discover Our Wide Range of Product Forms and Ideal Sizes
Looking for the perfect product form and size? We’ve got you covered!
Our product is available in various forms such as Sheet / Plate, Bar, Wire, Tube / Pipe, and Strip. With a wide thickness range (0.5 – 60mm for sheets), customizable tolerance, and different surface finishes, we can tailor to your unique needs. Plus, our flexible MOQ and reliable packaging ensure a smooth purchasing experience. Don’t miss out on finding the ideal product for your project!
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- Certified to ISO 9001, ROHS,AMS, ASTM, NACE MR0175 standards and other standards.
- Full material traceability from melt to shipment.
- Flexible MOQ – from R&D samples to bulk orders.
- Global shipping available. We reply to all inquiries within 24 hours.
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