elinvar

metallurgy

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Last updated

June 26, 2026

Quick Summary

Elinvar is a specialized alloy primarily composed of iron, nickel, and chromium. It is known for its exceptionally low thermal expansivity, meaning it expands very little when heated. Additionally, its modulus of elasticity remains remarkably stable across a wide range of temperatures.

These unique properties make elinvar ideal for applications requiring high precision, such as springs in watches and other sensitive instruments. The name "elinvar" itself is derived from the French words for "invariable elasticity," reflecting its key characteristic. Invar, a similar alloy containing 64% iron and 36% nickel, was historically used for length standards and is still found in surveying tapes and temperature-sensitive devices.12

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Charles Édouard Guillaume
…alloys and developed invar and elinvar. Invar’s low coefficient of expansion (change in volume caused by change in temperature) and elinvar’s low coefficient of elasticity (change in elasticity caused by change in temperature), combined with their low cost, resulted in their widespread use in scientific instruments.
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…alloys and developed invar and elinvar. Invar’s low coefficient of expansion (change in volume caused by change in temperature) and elinvar’s low coefficient of elasticity (change in elasticity caused by change in temperature), combined with their low cost, resulted in their widespread use in scientific instruments.
Read More