Nivarox, also known as Nivarox - FAR SA is a Swiss company formed by a merger in 1984 between Nivarox SA and Fabriques d' Assortiments Réunis (FAR). It is currently owned by the

Swatch Group The Swatch Group Ltd is a Swiss manufacturer of watches and jewellery. The company was founded in 1983 by the merger of ASUAG and SSIH to move to manufacturing quartz-crystal watches to resolve the quartz crisis threatening the traditional Sw ...

. Nivarox is also the trade name of the metallic alloy from which its products are fabricated. Its notable property is that its coefficient of elasticity is remarkably constant with temperature. Nivarox is most famous for producing hairsprings that are attached to the

balance wheel A balance wheel, or balance, is the timekeeping device used in mechanical watches and small clocks, analogous to the pendulum in a pendulum clock. It is a weighted wheel that rotates back and forth, being returned toward its center position by a ...

inside a mechanical watch movement, as well as mainsprings which provide the motive power for the watch. Nivarox was developed for use in watch hairsprings in 1933 by Reinhard Straumann in his Waldenbourg laboratory. FAR was the corporate name chosen in 1932 for the entity comprising several companies and subsidiaries located in

Le Locle Le Locle (; german: Luggli) is a Communes of Switzerland, municipality in the Canton of Neuchâtel in Switzerland. It is situated in the Jura Mountains, a few kilometers from the city of La Chaux-de-Fonds. It is the third smallest city in Switz ...

Switzerland ). Swiss law does not designate a ''capital'' as such, but the federal parliament and government are installed in Bern, while other federal institutions, such as the federal courts, are in other cities (Bellinzona, Lausanne, Luzern, Neuchâtel ...

, which at the time manufactured various watch components.

Nivarox alloy

As a trade name, Nivarox is an

acronym An acronym is a word or name formed from the initial components of a longer name or phrase. Acronyms are usually formed from the initial letters of words, as in ''NATO'' (''North Atlantic Treaty Organization''), but sometimes use syllables, as ...

from the

German German(s) may refer to: * Germany (of or related to) ** Germania (historical use) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizens of Germany, see also German nationality law **Ge ...

german: Nicht variabel oxydfest, label=none, lit=Non-Variable Non-Oxidizing. The Nivarox alloy is a

nickel Nickel is a chemical element with symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel is a hard and ductile transition metal. Pure nickel is chemically reactive but large pieces are slow to ...

iron Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in f ...

alloy An alloy is a mixture of chemical elements of which at least one is a metal. Unlike chemical compounds with metallic bases, an alloy will retain all the properties of a metal in the resulting material, such as electrical conductivity, ductility, ...

used mainly in the watch industry for hairsprings for balance wheels, but also in other micro-machine industries and in certain medical equipment and surgical instruments, in the same category as

Elinvar Elinvar is a nickel–iron–chromium alloy notable for having a modulus of elasticity which does not change much with temperature changes. The name is a contraction of the French ('invariable elasticity'). It was invented by Charles Édouard Guil ...

, Ni-Span, Vibralloy,

Nivaflex Nivaflex is an octavariant alloy important in watchmaking, used primarily for the mainspring. The name was registered as a trademark in 1957 by Reinhard Straumann, a Swiss metallurgist. Nivaflex is "wholly non-magnetic" and displays a very low c ...

and other similar alloys. The "non-variable" refers to the alloy's most notable property: that it has a low temperature coefficient of elasticity; its elasticity does not change much with temperature. There are several versions of the Nivarox alloy depending upon the intended application: Nivarox-CT, but also with suffixes CTC, M, W. Chemical compositions vary in wt% as follows for all Nivarox alloys : Iron as balance, a wide variation in nickel between 30-40%, beryllium 0.7-1%, some versions have molybdenum at 6-9% while others have instead chromium 8%, titanium is present in some compositions at 1%, manganese at 0.7-0.8%, silicon 0.1-0.2% and carbon in traces up to 0.2%. A typical composition would be for the early version Nivarox-CT (by wt %) : Fe 54%, Ni 38%, Cr 8%, Ti 1%, Si 0.2%, Mn 0.8%, Be 0.9%, C < 0.1%. When used for critical watch components, the alloy reduces errors due to temperature variation.

Hairspring A balance spring, or hairspring, is a spring attached to the balance wheel in mechanical timepieces. It causes the balance wheel to oscillate with a resonant frequency when the timepiece is running, which controls the speed at which the wheels of t ...

s made of this alloy have a

spring constant In physics, Hooke's law is an empirical law which states that the force () needed to extend or compress a spring (device), spring by some distance () Proportionality (mathematics)#Direct_proportionality, scales linearly with respect to that ...

which does not vary with temperature, allowing the watch's

, its timekeeping element, to keep better time. Along with the earlier alloy

, this alloy made obsolete the expensive compensation balance used in precision timepieces in the 19th century. Nivarox springs are now used by most

watchmakers A watchmaker is an artisan who makes and repairs watches. Since a majority of watches are now factory-made, most modern watchmakers only repair watches. However, originally they were master craftsmen who built watches, including all their par ...

worldwide, with a global market share of 90%. The alloys also see limited use for specific components of sensitive scientific instruments.

References

{{reflist Nickel alloys Horology Manufacturing companies of Switzerland