Super Invar (aka Super Invar 32-5)
Super Invar 32-5 is a low expansion alloy consisting of 32% Nickel, 5% Cobalt, and balance Iron. Super Invar Alloy exhibits minimum thermal expansion at room temperatures (one half of Invar Alloy), as well as thermal expansion properties less than that of Invar Alloy in the 67/203°F (-55/95°C) temperature range. The minimal expansion of Super Invar over this range of temperatures, makes this alloy useful in many applications including structural components and substrates in instrument systems requiring precision measurements.
Super Invar Products
Ed Fagan Inc. stocks Super Invar in a variety of forms and dimensions. Below are most of the standard stock form/sizes. If you do not see the size or form of Super Invar that you require, please call one of our materials experts; our sales people are very knowledgeable and can assist you. We can cut, slit, shear, or center less grind Super Invar to your exact specifications, and we also have tremendous versatility when it comes to custom sizes, packages, and unusual materials
Super Invar Rod - 0.50" - 3.50"
Super Invar Sheet - 0.039" - 0.118"
Super Invar Plate - 0.50" - 2.50"
Super Invar Applications
Optical instruments . Telescopes . Laser instruments and equipment . Ring laser gyroscopes . Laser benches . Positioning devices . Metrology devices . Structural components . Substrates in instrument systems requiring precision measurements, and other applications that require lower expansivity than Invar Alloy provides.
Super Invar Properties
Super Invar Alloy Physical Properties | ||
Density |
lb/cu in |
0.294 |
Specific Gravity |
|
8.15 |
Curie Temp |
°F |
470 |
|
°C |
245 |
Melting Point |
°F |
2600 |
|
°C |
1427 |
Electrical Resistivity |
Micro-ohm-cm |
82 |
|
ohm-cir mil/ft |
481 |
Thermal Conductivity |
W/cm °C |
0.10 |
|
BTU-in/sq. ft-hr- |
72.6 |
Specific Heat |
Cal/g- °C |
0.12 |
|
BTU/lbm- °F |
0.12 |
Thermal Expansion |
ppm / °F (75°F to 842°F) |
4.5 |
|
ppm / °C (25°C to 450°C) |
8.0 |
Super Invar Mechanical Properties | ||
Tensile Strength |
ksi |
70 |
|
MPa |
483 |
Yield Strength |
ksi |
40 |
|
MPa |
276 |
Elongation |
% in 2 in. |
40 |
Typical Hardness Ann. |
Rockwell HRB |
75 |
Modules of Elasticity |
Mpsi |
21 |
|
kMPa |
145 |
Super Invar Chemistry | |
maximum % unless noted |
|
Iron |
Bal |
Nominal Nickel |
32 |
Nominal Cobalt |
5.0 |
Carbon |
0.05 |
Silicon |
0.25 |
Sulfur |
0.015 |
Chromium |
0.25 |
Super Invar Specifications |
ASTM F-1684 |
Super Invar Alloy Linear Coefficient of Thermal Expansion | |||
Degree C |
Degree C |
||
30-100 |
0.84 |
30-450 |
-- |
30-150 |
1.17 |
30-475 |
-- |
30-200 |
1.72 |
30-500 |
8.99 |
30-250 |
2.53 |
30-525 |
-- |
30-300 |
4.16 |
30-550 |
10.56 |
30-325 |
-- |
30-600 |
-- |
30-350 |
5.74 |
30-700 |
-- |
30-375 |
-- |
30-800 |
-- |
30-400 |
7.03 |
30-900 |
-- |
30-425 |
-- |
30-1000 |
-- |
ED FAGAN INC. supplies the highest quality special purpose metals and alloys for Aerospace/Aviation, Defense, Electronics, Magnetic, Medical, Lighting, Optical, Telecommunications, Ceramics, Heat Treating, and other high-technology industries.

Controlled Expansion Alloys
Ed Fagan Inc. stocks a variety of similar alloys for low expansion, controlled expansion, glass-to-metal or ceramic sealing applications that may also satisfy your needs. EFI carries:Invar
Super Invar
Kovar
42 Alloy
46 Alloy
48 Alloy
52 Alloy
And we also have a large selection of other types of specialty metals and alloys for high technology applications, including:
Electrical/Electronic Nickel
Soft Magnetic Alloys
Refractory Metals and Alloys
Hard to Find Materials