invarAn alloy composed of 64% iron, 36% nickel, and a trace of carbon. Having a very small coefficient of linear expansion, invar is used for pendulums, tuning-forks, measuring devices, and other components whose dimensions must be independent of temperature. It was discovered by the Swiss physicist Charles Guillaume (1861–1938) who was awarded the 1920 Nobel Prize in Physics for the discovery. Related categories INDUSTRIAL CHEMISTRY• INORGANIC CHEMISTRY Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History |