4J29 Rod Kovar Alloy Bar Fe Ni Co Controlled Expansion Alloy for Glass to Metal Sealing

Product Description

4J29 alloy rod, also known as Kovar rod, is a Fe-Ni-Co controlled expansion alloy with a thermal expansion coefficient closely matching that of hard glass and ceramics. It provides excellent glass-to-metal and ceramic-to-metal sealing properties, ensuring reliable hermeticity.

With stable mechanical performance, good machinability, and outstanding sealing reliability, 4J29 rods are widely applied in electronic packaging, vacuum devices, semiconductor bases, sensors, and aerospace instruments.

Key Features

• Fe-Ni-Co controlled expansion alloy

• Thermal expansion matches hard glass and ceramics

• Excellent hermetic sealing performance

• Stable mechanical strength at different temperatures

• High machinability and surface finish

• Available in rods, wires, sheets, and customized forms

Typical Applications

• Glass-to-metal hermetic sealing

• Semiconductor packaging bases

• Electronic packaging components

• Vacuum tubes and light bulbs

• Aerospace and defense devices

• Sensors, relays, and feedthroughs

Chemical Composition (%)

Physical and Performance Properties

Available Specifications

Huona (Shanghai) New Material Co., Ltd. Was established in 2008, currently have three divisions: Magnesium Division, Thermal Spray Division and Functional Material Division.

Magnesium Division produces magnesium metal products. Various models of high-quality magnesium alloy plate, magnesium rods, high-purity magnesium, magnesium plate, magnesium die casting, magnesium extrusion profiles and other metal magnesium and deep processing products.

Thermal spray wire Division offers a wide variety of pure metal and metal alloy wires, including nickel-, iron-, aluminum-, and zinc-based wires for thermal spray projects.

Fuctional Material Division supply electronic packaging COMPONENTS(GTMS, CTMS), soft magnetic alloys and bimetal strip.

Our company is certified by ISO9001 quality system and ISO14001 environmental protection system.

Mission Statement

We try our best to understand and utilize information within the environment. With this competency, we assist customers to create added value and contribute to the development of industry and healthy living.

We strive for "Best, " welcome challenges, and are relentless till we deliver products and solutions.