Kovar Bar

Character of Kovar

Kovar alloy is a vacuum melted, iron-nickel-cobalt, low expansion alloy whose chemical composition is controlled within narrow limits to assure precise uniform thermal expansion properties. Extensive quality controls are employed in the manufacture of this alloy to ensure uniform physical and mechanical properties for ease in deep drawing, stamping and machining. Kovar alloy has been used for making hermetic seals with the harder Pyrex glasses and ceramic materials. This alloy has found wide application in power tubes, microwave tubes, transistors and diodes. In intergrated circuits, it has been used for the flat pack and the dual-in-line package.

Kovar alloy is magnetic at all  temperatures below the Curie point. Magnetic properties will depend upon heat  treatment; the lower hardness, the higher permeability values and  lower hysteresis loss.

Density: 8.36g/cm3

Curie Temp: 435°C(815°F)

Introduction of Kovar

Kovar is a Ni-Fe alloy with 29% Nickel, 17% Cobalt and the remaining balance is Iron. The expansion  characteristics of Kovar match both borosilicate (or Pyrex) glasses and  alumina ceramics, making it one of the most popular of the controlled expansion alloys for hermetic sealing applications.

Chemical  composition of Kovar alloy 

C≤0.020, Ni≤29.0,  Si≤0.20, Mn≤0.30, Co≤17.0, Fe=remainder

Delivery

Huge stock of strip, bar and wire in stock. Fast delivery with 5 days for customized size.

Forms available: Plate, sheet, strip, wire, rod, bar,  forging, tube, pipe, capillary, square pipe, and parts

Application of Kovar  

Kovar is widely used in applications such as power tubes, microwave tubes, transistors, diodes, hybrid packages and other kinds of scientific instruments.

Equal grades

4J29(China grade), ASTM F-15, NILO K, Pernifer 2918, Rodar, Dilvar P1, UNS K94610, 29-17 alloy

Standards

ASTM-15