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Iron Nickel Base Nilo50 Low Expansion Alloys 4J50 For Electric Vacuum Industry

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China Ohmalloy Material Co.,Ltd certification
China Ohmalloy Material Co.,Ltd certification
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Iron Nickel Base Nilo50 Low Expansion Alloys 4J50 For Electric Vacuum Industry

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Large Image :  Iron Nickel Base Nilo50 Low Expansion Alloys 4J50 For Electric Vacuum Industry Get Best Price

Product Details:
Place of Origin: China(Shanghai)
Brand Name: OHMALLOY
Certification: ISO9001-2008
Model Number: 4J50
Payment & Shipping Terms:
Minimum Order Quantity: 20KG
Price: negotiable
Packaging Details: in spool/ carton packed
Delivery Time: 7-10 days
Payment Terms: L/C, T/T, , MoneyGram
Supply Ability: 50 Tons per month
Detailed Product Description
Material: FeNi50 Density (g/cm3): 8.21
Electrical Resistivity At 20℃(Ωmm2/m): 0.44 Tensile Strength: 490Mpa
Elongation: 35%
High Light:

invar alloy


thermal expansion invar

OhmAlloy-4J50 (Expansion alloy)

(Common Name: 50H, N50, Vacovit 500, FeNi50)


4J50 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.

4J50 alloy is widely used the structure of the sealing material in the electric vacuum industry.

Normal composition%

Ni 49.5~50.5 Fe Bal. Co 1.0 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) 8.21
Electrical resistivity at 20℃(Ωmm2/m) 0.44
Thermal conductivity, λ/ W/(m*℃) 16.7
Curie point Tc/ ℃ 500
Elastic Modulus, E/ Gpa 158



Coefficient of expansion

θ/℃ α1/10-6-1 θ/℃ α1/10-6-1
20~100 9.8 20~400 9.4
20~200 9.8 20~450 9.4
20~300 9.5 20~500 9.7
20~350 9.4 20~600 10.6


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  
OhmAlloy-4J50 Wire D= 0.1~8mm  
OhmAlloy-4J50 Strip W= 5~250mm T= 0.1mm
OhmAlloy-4J50 Foil W= 10~100mm T= 0.01~0.1
OhmAlloy-4J50 Bar Dia= 8~100mm L= 50~1000

Contact Details
Ohmalloy Material Co.,Ltd

Contact Person: Mr. Qiu

Tel: +8613795230939

Send your inquiry directly to us