Invar

See Also: Montres Invar

Invar is a nickel-iron alloy with a low coefficient of thermal expansion. It was invented in 1895 by Swiss physicist Charles Édouard Guillaume, who received the Nobel Prize in 1920. The name comes from the word "invariable" and was commonly used in the watch industry to denote strength and reliability.

Invar is widely used for balance wheels in watches and pendulums in clocks.

See Also

• Montres Invar, the later name for Achille Hirsch's watch company in La Chaux-de-Fonds