NiFe Alloy 4J29/Kovar - W.Nr 1.981

Alloy 4J29 is an iron-nickel-cobalt alloy with a coefficient of thermal expansion similar to that of hard (borosilicate) glass. This makes it especially suitable for uses which require a matched-expansion seal between metal and glass parts.

Alloy 4J29 usage in the electronics industry for metal parts bonded to hard glass envelopes for such devices as power tubes, x-ray tubes, etc, and other applications requiring glass-to-metal seals.

 

Basic performance: Precision Alloy is divided into low-expansion alloy and fixed-expansion alloy, the latter is also known as sealing alloy. Precision Alloy Expansion alloy besides has the specific thermal expansion coefficient, according to the different USES also requires a good sealing property, weldability and corrosion resistance, machinability and cutting, and in the use of expansion characteristics caused by the temperature range there is no obvious change of phase transformation, Precision Alloy product is commonly bar, sheet, strip, wire and tube and so on.

 

Precision Alloy Expansion alloy applications: Precision Alloy is widely used in glass, metal and ceramic sealing in avionics and instruments, electric vacuum industry and other electronic devices, electric light source and other fields.