FeNi42 Iron nickel alloy is obtained at a given temperature range by adjusting the content of nickel internal energy and the expansion coefficient of different soft glass and ceramic matching a series of expansion alloy, its expansion coefficient and the Curie temperature increases with the increase of nickel content.The assembly is widely used in electric vacuum industry the sealing structure of the material.

Chemical composition

Composition % Fe Ni Mn C P S Si Al
content min Bal 41.5 - - - - - -
content max Bal 42.5 0.8 0.05 0.02 0.02 0.3 0.1

Physical and chemical properties

Property Name Value
Density (g/cm3) 8.12
Electrical resistivity at 20ºC(mm2/m) 0.61
Hardness(HV) 135
Thermal conductivity, λ/ W/(m*ºC) 14.6
Curie point Tc/ ºC 360
Elastic Modulus, E/ Gpa 147
Melting point ºC 1430

Main purpose:

mainly used for soft glass and ceramic sealing, Make electronic tubes, transistors and integrated circuit leads, Frame and seal plug.

Supply status

There are rods, tube, rods, strip and wire.

Coefficient of expansion

θ/ºC α1/10-6ºC-1 θ/ºC α1/10-6ºC-1
20~100 5.6 20~400 5.9
20~200 4.9 20~450 6.9
20~300 4.8 20~500 7.8
20~350 4.95 20~600 9.2

Typical Mechanical properties

Tensile Strength Elongation
Mpa %
490 35

The heat treatment process

Annealing Heated to 900 ±20ºC in a hydrogen atmosphere
Holding time, h 1 hour
Cooling With speed not more than 5 ºC / min. cooling to below 200 ºC