Invar 36 is a nickel-iron low expansion alloy containing 36% nickel that maintains nearly constant dimensions across normal atmospheric temperatures. This material features an exceptionally low coefficient of thermal expansion from cryogenic temperatures up to approximately 500°C while retaining excellent strength and toughness at cryogenic temperatures.

• Low expansion rate up to 500°C
• Excellent dimensional stability across temperature ranges
• Maintains strength and toughness at cryogenic temperatures
• Readily weldable using various methods
• Compatible with hot and cold forming processes

• Tooling and dies for composite forming
• Cryogenic components and systems
• Laser components and optical systems
• Precision instruments requiring dimensional stability
• Electrical vacuum industry components

Invar 36 can be hot and cold formed and machined using processes similar to austenitic stainless steels. The alloy is weldable using Filler Metal CF36 available in bare wire for both GTAW and GMAW processes. Recommended welding methods include oxyacetylene welding, electric arc welding, and Argon arc welding with filler metals containing 0.5% to 1.5% titanium to reduce weld porosity and cracking.