Invar

What is it?

A specialty nickel-iron alloy engineered around a single property: it barely expands or contracts with temperature change.

Key behavior

Near-zero thermal expansion at ambient temperatures — where most metals grow and shrink noticeably with heat, Invar essentially doesn't.

Why choose it

Precision instruments, optical equipment, or tooling where dimensional accuracy has to hold steady across temperature swings.

Applications

Optical instrument frames, laser equipment mounts, aerospace composite tooling, precision measuring equipment.

Machining notes

Prone to work hardening — slower cutting feeds are typically needed compared to standard steel. Invar’s near-zero expansion, not its strength, is normally the reason it is specified: semiconductor equipment and precision instrument parts where thermal drift sets the tolerance.