Xi'an Gangyan specilalized in manufacturing high-quality percision alloy for 23+ years.
Location: Home » Product Center » Expansion Alloy
Contact XAGY



Location:No. 88 East of Century Avenue, XianYang, Shaanxi, China. P.C. 712046

Invar Alloy

Invar alloy,ASTM F1684,UNS k93600(FeNi36),Chinese 4J36
A Nickel-Iron, low expansion alloy containing 36% Nickel. It maintains nearly constant dimensions over the range of normal atmospheric temperatures.
Forms: Sheet/Plate, Bar/Rod/Wire/Coil,Capillary/Pipe/Tube
Order Email:sales@xagy.cn


Invar (also know as Invar 36, NILO 36, Pernifer 36, and Invar Steel) is a low expansion alloy consisting of 36% Nickel, balance Iron. Invar Alloy exhibits extremely low expansion around ambient temperatures, making Invar Alloy particularly useful in applications where minimum thermal expansion and high dimensional stability is required, such as in precision instruments like optoelectronic devices, optical and laser benches, electronics, and other kinds of scientific instruments.


This alloy has been used for applications where dimensional changes due to temperature variation must be minimized such as in radio and electronic devices, aircraft controls, optical and laser system, etc.


Cross Reference

Russia USA Japan France Germany U.K.
36H Invar Cactus LE Invar Standard Vacodil36 Invar
Nilvar Nilo36
36H-ВИ Unipsan36 Fe-Ni36 Nilos36 36Ni

Typical chemistry

C Si P S Mn Ni Fe
0.05 0.30 0.020 0.020 0.20~0.60 35.0~37.0 Balance

Physical Property

Density lb/cu in 0.291
Specific Gravity   0.825
Curie Temp °F 535
°C 279
Melting Point °F 2600
°C 1427
Electrical Micro-ohm-cm 84
Resistivity Micro-ohm-cm 495
Thermal W/cm °C 0.10
Conductivity BTU-in/sq. ft-hr- 72.6
Specific Heat Cal/g- °C 0.123
BTU/lbm- °F 0.123

Average Coefficient of Linear Expansion

Heat Treatment of the Samples Mean Coefficient of Linear Expansion
20 to l00℃ 20 to 300℃
To heat the semi-finished products samples to 840±10°C, hold for1hour, and quench in the water. Machine the samples to finished samples. And heat at 315±10℃ for 1h, furnace or air cool. 1.5(max)  

Mean Coefficient of linear expansion at different temperature, ā/(10-6/K)

Invar alloy

Size Range

Sheet Thickness:0.10mm~3.50mm, width: ≤300mm
Plate Thickness:3.5mm~40.0mm, width: ≤500mm
Round wire Thickness:0.10mm~5.0mm
Flat Wire Dia 0.5mm~Dia 5.0mm, length≤1000
Rod Dia 5.0mm~Dia 8.0mm, length≤2000
Dia 8.0mm~Dia 32.0mm, length≤2500
Dia 32.0mm~Dia180.0mm, length≤1000
Capillary OD 8.0mm~1.0mm,ID 0.1~8.0 length≤2500
Pipe OD 120mm~8.0mm,ID 8.0~129 length≤4000

Condition: (With max tolerance) cold rolled, cold drawn, hot rolled , hot forging ,peeled turned ,bright ,bright annealed

XAGY Advantages

1. High-qulity product

  • ISO9001:2008 International Quality System Certification.
  • With advanced equipments: VIMF, Induction Furnace, ESR Furnace ect.
  • Strict Quality-testing System.

2. Strong R & D Strength

  • 40,000㎡ production base.
  • 60+ R & D team members, with rich customization experience.
  • A good assortment of alloy to choose.

3. Efficient delivery

  • Flexible transport means, very convenient.
  • Tailor a suitable transport plan.

4. Good service

  • We provide online service, information feedback within 24 hours.
  • Professional team to provide remote technical advice and guidance.

Contact XAGY

Xi'an Gangyan Special Alloy Co., Ltd.

Hotline: 0086-29-33669103

Fax: 0086-29-33698670

Email: sales@xagy.cn

Add.: No. 88 East of Century Avenue, XianYang, Shaanxi, China. P.C.712046

Purchase:Invar Alloy

  • *Contact person:
  • Mobile phone:
  • Company name:
  • *Email:
  • *Purchase intention:
  • *Verification code:Verification code