2025-04-15

prettygoodword: text: words are sexy (Default)
2025-04-15 06:37 am

invar

invar (in-VAHR) - n., an alloy of iron with 35.5% nickel.


This has a very low coefficient of expansion, making it very useful for precision parts that need to not change size with the temperature, such as watch springs. This is a current trademark and so technically should be spelled Invar, but some dictionaries acknowledge it is often spelled as a generic. If you want to use a generic name instead, that would be FeNi36 (outside USA) or 64FeNi (in the USA). Coined as a shortening of invariable.

---L.