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ASTM F-15 Controlled Expansion Alloys UNS K94610 Glass Sealing Rolled Strip

Place of Origin China
Brand Name XUNSHI
Model Number Kovar
Minimum Order Quantity 20kg
Price USD 20-50 per kg
Packaging Details Wooden case
Delivery Time 3-5 weeks
Payment Terms T/T
Supply Ability 10000kg per week

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Product Details
Material Fe-Ni-Co Forms Strip, Bar, Wire, Pipe
Equal Grades 4J29(China), ASTM F-15, NILO K, Pernifer 2918, Rodar, Dilvar P1, UNS K94610, 29-17 Alloy Product Name Controlled Expansion Alloys
Model Kovar Brand AIWEN
High Light

iron nickel alloy


thermal expansion nickel

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Product Description

Kovar Controlled Expansion Alloy ASTM F-15 UNS K94610 Glass Sealing Alloy


Kovar controlled expansion alloy, most likely know as 4J29 in China, is a Nickel Iron alloy with 29% Nickel, 17% Cobalt and the remaining balance is Iron.


Kovar controlled expansion alloy, was invented to meet the need for a reliable glass-to-metal seal, which is required in electronic devices such as light bulbs, vacuum tubes, cathode ray tubes, and in vacuum systems in chemistry and other scientific research area.


Kovar has thermal expansion similar to glass. Meanwhile its nonlinear thermal expansion curve can often be made to match a glass. This makes it the most popular controlled expansion alloy so far.


Chemical compostion of Kovar

Alloy % Ni Cr Co Cu C Mn Si P S Mo Fe
Kovar Min 28.5   16.8               Rem
Max 29.5 0.2 17.8 0.20 0.03 0.50 0.30 0.02 0.02 0.20


The average linear expansion coefficient(10-6C)

20~100°C 20~300°C 20~400°C 20~450°C 20~500°C 20~530°C 20~600°C
4.6~5.2 5.1~5.5


Applications of Kovar

  •  Light bulbs
  •  Vacuum tubes
  •  Cathode ray tubes
  •  Power tubes
  •  Microwave tubes
  •  Transistoers
  •  Diodes
  •  Hybrid packages
  •  Other kinds of scientific instruments

Forms available at A-ONE ALLOY

  •  Bar
  •  Tube
  •  Strip
  •  Wire
  •  Plate
  •  Capillary