Glossary of watchmaking


Invar | インバー | 不变钢

Alloy of iron and nickel whose low coefficient of thermal expansion was discovered by Charles Edouard Guillaume. Invar (abbreviation of invariable) belongs to the Elinvar family of metals which encompasses ferronickel alloys whose thermoelastic coefficient is a negligible -10°C to +30°C.

These alloys are used to make compensation balances for watches.