4J29 Kovar is a low-expansion iron-nickel-cobalt alloy, typically containing approximately 29% nickel, 17% cobalt and balance iron. It offers a low and stable thermal expansion coefficient over a wide temperature range. This product is manufactured by precision rolling into thin foil with thicknesses of 10μm and 15μm. It features flat surface, controlled thickness tolerance and is suitable for stamping, etching, welding and precision processing.

✅ Material Properties

1. Low expansion coefficient, good matching with glass and ceramics for hermetic sealing
2. Thin and uniform dimensions, suitable for precision electronic components and microstructures
3. Smooth surface and high flatness, suitable for etching, stamping and welding
4. Good room-temperature strength and ductility for micro foil parts, leads and sealing components

✅ Product Specification

• Grade: 4J29 (Kovar)
• Type: Alloy foil / thin strip
• Thickness: 10μm, 15μm
• Different widths, lengths, coil or sheet packaging available on request

✅ Inspection & Certificates
Heat-numbered MTC, chemical composition report, thickness inspection report, dimensional tolerance report and related material performance reports can be provided.

✅ Application Fields

• Semiconductor Packaging: Lead frames, sealing gaskets, transition connectors
• Vacuum Electronics: Anodes, grids, sealing parts
• Precision Instruments: Relays, sensors, elastic components
• Aerospace Electronics: Lightweight precision sealing parts, electronic packaging components

We supply 4J29 Kovar foil, strip, bar and custom precision alloy materials. Sample and bulk orders are accepted. Please contact us for detailed specification tables and quotation.