INVAR 36 is a nickel-iron, low-expansion alloy containing 36% nickel. It maintains nearly constant dimensions over the range of normal atmospheric temperatures, and has a low coefficient of expansion from cryogenic temperatures to about 500°F. The alloy also retains good strength and toughness at cryogenic temperatures.

INVAR 36 can be hot and cold formed and machined using processes similar to austenitic stainless steels. INVAR 36 is weldable using Filler Metal CF36 which is available in bare wire for both the GTAW and GMAW process.


INVAR 36 Plate, INVAR 36 Weld Wire

Common Trade Names

Nilo 36


  • Low expansion rate up to 500°F
  • Readily weldable


  • Tooling and dies for composite forming
  • Cryogenic components
  • Laser components