Kovar 4J29 (K94610)
4J29 KOVAR
4J29 also known as kovar alloy,ASTM F15,Nilo-K, UNS K94610 ,(FeNi29Co17),
YB/T5231-2005 ,(FeNi29Co18),Lockinvar,Alloy 12B,Sealing Alloy. Iron Nickel cobalt .
A Nickel-Iron-Cobalt, controlled expansion alloy containing 29% Nickel. It's coefficient of expansion (which decreases with rising temperature to the inflection point), matches the expansion rate of borosilicate glasses and aluminia ceramics. Applications include glass to metal seals in applications requiring high reliability or resistance to thermal shock, ie. high-power transmitting valves, transistor leads and heaters and photography flash bulbs.
Description
Alloy 2917 (Kovar) 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, coining, stamping and machining.
Chemistry: Typical
Carbon: 0.02 max
Silicon: 0.20 max
Manganese: 0.30 max
Nickel: 29.0 max
Cobalt: 17.0 max
Iron: Balance
The iron, nickel and cobalt requirements listed may be adjusted so that the alloy meets the specified requirements for coefficient of thermal expansion
Physical Properties
Density: 0.302 lb/in³, 8.60 g/cm³
Modulus of Elasticity: ksi (MPa)
20 x 10³Ksi (138 x 10³) in tension
Melting Range: 1450 Centigrade degree
Product Forms
Sheet, Strip, Plate: Inquiry with Ulbrich Stainless Steel Sales
Wire, Profile, Round, Flats Squares
Mechanical Properties at Room Temperature
Properties: Annealed Typical
Ultimate Tensile Strength: 75 KSI nom (517 MPa nom)
Yield Strength: 49 KSI nom ( 340 MPa nom )
Elongation: 42% min
Properties: Tempered
Alloy 2917 (Kovar) can be cold worked to various tempers. Contact Ulbrich Technical Service for additional information
Additional Properties
Corrosion Resistance
Refer to NACE (National Association of Corrosion Engineers) for recommendations.
Applications
Alloy 2917 (Kovar)has been used for making hermetic seals with the harder Pyrex glasses and ceramic materials. This alloy has found wide use in application where high reliability is a necessity. In power tubes, microwave tubes, transistors, diodes, inter-grated circuits and has been used for the flat pack and the dual-in-line package.
