FeNi42/ 4J42/ 42Н

FeNi42/ 4J42/ 42Н

Short Description:

4J42 alloy is mainly composed of iron, nickel elements. It is characterized with a fixed coefficient of expansion. Increase the thermal expansion coefficient and the Curie point with increase of nickel content.

Product Detail

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4J42 Expansion alloy
(Common Name: 42H Glass Sealing 42, Nilo42, N42, FeNi42)

4J42 alloy is mainly composed of iron, nickel elements. It is characterized with a fixed coefficient of expansion. Increase the thermal expansion coefficient and the Curie point with increase of nickel content.

4J42 alloy is widely used the structure of the sealing material in the electric vacuum industry.
Normal composition%

Ni 41.5~42.5 Fe Bal. Co - Si ≤0.3
Mo - Cu - Cr - Mn ≤0.8
C ≤0.05 P ≤0.02 S ≤0.02 Al ≤0.1

Typical Physical properties

Density (g/cm3) 8.12
Electrical resistivity at 20℃(Ωmm2/m) 0.61
Thermal conductivity, λ/ W/(m*℃) 14.6
Curie point   Tc/ ℃ 360
Elastic Modulus,  E/ Gpa 147

Coefficient of expansion

θ/℃ α1/10-6-1 θ/℃ α1/10-6-1
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 ±20℃ in a hydrogen atmosphere
Holding time, h 1 hour
cooling With speed not more than 5 ℃ / min. cooling to below 200 ℃

Style of supply

Alloys Name Type Dimension
4J42 Wire D= 0.1~8mm
Strip W= 5~250mm T= 0.1mm
Foil W= 10~100mm T= 0.01~0.1
Bar Dia= 8~100mm L= 50~1000

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    The product forms include wire, flat wire, strip, plate, bar, foil, seamless tube , Wire mesh, powder, etc., can meet the application needs of different customers.

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