In the common sense metal expand when heated however, we are able to offer metal which has no thermal expansion.
We have developed various low and zero thermal expansion alloy (invariable alloy) which applicable various kinds of application.
Followings are our series of low thermal expansion alloys (Invariable alloy) however, we are also able to make customized invar according to customer’s requirement which have additional special characteristics.


IC-ZX Zero thermal expansion with high rigidity alloy regardless weight and thickness.
・Palm to 3ton big size zero expansion cast alloy
CTE : 0/1,000,000 (0±0.15ppm)
Young’s modulus : More than 130GPa
No martensite transformation up to -20℃, high environmental resistance.
Ultra low carbon content realizes temporal dimensional stability
Squire and round bar forged, rolled plate, bar and sheet is available.
IC-EX1 High rigidity low thermal expansion alloy (High rigidity invariable alloy) regardless weight and thickness.
Palm to 3t big size high rigidity low thermal expansion cast alloy can be manufactured.
Young’s modulus : more than 140GPa.
CTE : 1.5 to 2.0ppm
IC-LTX Zero thermal expansion alloy used for sub-zero temperature range.
No martensite transformation up to -100℃
CTE at 0-60℃ : 0/1,000,000 (α≦0.1ppm)
Squire block and round forged, rolled plate, bar and sheet is available.
Applied to severe low temperature suitable for aviation and aero space requirement.
IC-36S Very low thermal expansion alloy which CTE is less than 1ppm. (Super invar alloy). CTE is lower than general 36% Ni invar (CTE 1.5ppm).
Cast alloy, forged alloy, rolling, wire drawing and sheet etc. variety form is available. Also this alloy has high weldability and has good match with canned product. TIG, MIG welding rod is also available with us.
IC-36FS Super invariable alloy with increased machinability.
Applicable to every fabricated material as same as IC-36S. Super invariable alloy with increased machinability without loosing performance of IC-36S.
This alloy is developed to solve problem of customer who had difficult to reduce marching cost.
Among our invariable alloy series this grade is the most widely used grade and small lot or short time delivery can be made.
IC-36 Though CTE of this grade is quite standard 1.5ppm, microstructure of alloy is quite stable even less than -200℃.
Delivery with cast alloy, forged steel, rolling and wire drawing can be made.
The final number of grade name denotes for 2ppm, 4ppm, 5ppm of each CTE.
This is our strong point that we are able to control CTE by 1ppm.
In case use with ceramic or glass, you may chose same CTE from our invar series.
This alloy is appreciated very much for those had problem of difference of thermal expansion between the parts such as bi-metal.
SLE-2 This is stainless invar which has CTE less than 5ppm but keeping similar corrosion resistance as SUS304.
Among low thermal expansion alloy, this alloy has relatively high Young’s modulus as 170GPa and made high performance alloy in a total.
This alloy can be used in wet and sever PH environmental.
SLE-20A This alloy has similar corrosion resistance as SUS410 but also having CTE less than 3ppm.
Suitable for bush material for ceramics and lens glass to be mounted together.
IC-362A This stainless invar has high rust resistance in neutral atmosphere.
While keeping rust resistance performance we could manage to keep CTE less than 2ppm with this stainless invar.
ERIC-70 CTE is aimed 7ppm for those require vicinity CTE.
This invariable alloy has appropriate rust resistance and categorized as stainless invariable alloy products.
For examples, CTE of Titanium is 8ppm and this ERIC-70 is considered as suitable material for Titanium.
DIC-36 Spheroidized graphite precipitated low thermal expansion alloy is called as ductile invar which has excellent machinability.
Not only surface machining by milling cutter but also good for drilling of ultra fine tap.
Type Physical properties Mechanical properties
CTE Young’s modulus Thermal conductivity Specific heat 02%Y Yield strength Tensile strength Elongation Hardness
GPa W/m℃ J/kg℃ MPa MPa % HRB
Zero invar with high rigidity IC-ZX 0 137 15 500 224 393 39 75
Sub-zero temperature resistant zero invar IC-LTX 0 137 14 485 277 449 38 75
High rigidity invar IC-EX1 1.8★★ 145 14 490 196 410 44 70
Super invar IC-36S 0.7 120 14 450 230 440 50 73
IC-36FS 0.7 120 14 450 232 437 37 73
Invar IC-36 1.5 120 15 500 230 400 40 68
IC-362A 2.0 115 15 470 230 470 35 78
IC-364 4.0 135 14 480 162 413 39 69
Stainless invar SLE-2 5.0 170 14 470 169 400 40 68
SLE-20A 3.0 135 14 490 181 424 47 71
Invar stable in high temperature VIC-65 5.6★★★ 123 20 490 320 521 78

★:25〜50℃ ★★:23±5℃ ★★★:300〜350℃
(note)Hardness is actual measurement and not the value for quality assurance.

Reference :

Type CTE Young’s modulus Thermal conductivity Specific heat 02%Y Yield strength Tensile strength Elongation Hardness
GPa W/m℃ J/kg℃ MPa MPa % HRB
Ductile invar 3.5 114 16 480 269 453 30 76
Ferritic stainless (SUS410) 10.0 205 24 460 541 759 28 99
Austenitic stainless (SUS) 17.3 173 16 500 296 626 60 91
Spheroidal graphite cast iron (FCD450) 12.4 178 37 480 754 3 90
Carbon steel 12.2 207 55 490 637 666 17 99

Product (Material) Catalog

  • Stainless Invar
  • RappingPlate (Tin Alloy Plate)