Materials
Invar
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Invar is a nickel-iron alloy notable for its uniquely low coefficient of thermal expansion, a name derived from the word invariable. Swiss physicist Charles Edouard Guillaume discovered the alloy in 1895, work for which he received the Nobel Prize in Physics in 1920 for his discovery of anomalies in nickel-steel alloys. Because it barely expands or contracts as temperature changes, it became the material of choice for precision instruments: watch balance wheels and pendulum rods, surveying leveling rods, seismic creep gauges, color-television shadow-mask frames, and the structural components that support the dimension-sensitive optics of astronomical telescopes.
Facts
Primary UsePrecision instruments and clocks, surveying leveling rods, and structural components of astronomical telescopes, wherever near-zero thermal expansion matters. 1 Cross-Tradition Connections
Associated With
Invar is roughly 64 percent iron and 36 percent nickel; its low-expansion behavior comes from the nickel content.
In Field
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1. Invar (Wikipedia)
Wikipedia contributors, Wikimedia FoundationIntroductionQuote, Introduction
The discovery of the alloy was made in 1895 by Swiss physicist Charles Edouard Guillaume for which he received the Nobel Prize in Physics in 1920.
1. Invar (Wikipedia)
Wikipedia contributors, Wikimedia FoundationApplicationsQuote, Applications
Invar is used where high dimensional stability is required, such as precision instruments, clocks, seismic creep gauges, color-television tubes' shadow-mask frames, valves in engines and large aerostructure molds.
1. Invar (Wikipedia)
Wikipedia contributors, Wikimedia FoundationIn Category: MaterialView the Source 1. Invar (Wikipedia)
Wikipedia contributors, Wikimedia FoundationIn Field: Materials EngineeringView the Source 1. Invar (Wikipedia)
Wikipedia contributors, Wikimedia FoundationAssociated With: NickelView the Source Reader Challenges (0 open reader challenges)
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