Nivarox 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. Nivarox is also the trade name of the metallic alloy from which its products are fabricated. Nivarox is most famous for producing hairsprings which are attached to the balance wheel

Balance wheel

The balance wheel is the timekeeping device used in mechanical watches and some 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 spiral spring, the balance spring or hairspring...

 inside a mechanical watch movement, as well as mainsprings which provide the motive power for the watch.

The Nivarox story began in 1933 when Dr. Straumann perfected the process of hairspring manufacturing 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

Le Locle is a municipality in the district of Le Locle 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....

, Switzerland, manufacturing various watch components.

Nivarox alloy

As a trade name, Nivarox is a German acronym for "Nicht variabel oxydfest" (G.) or "Non-Variable Non-Oxidizing" (E.). The Nivarox alloy is a metallic alloy

Alloy

An alloy is a mixture or metallic solid solution composed of two or more elements. Complete solid solution alloys give single solid phase microstructure, while partial solutions give two or more phases that may or may not be homogeneous in distribution, depending on thermal history...

 used mainly in the watch industry, but also in other micro-machine industries and in certain medical equipment and surgical instruments. There are several variations of the Nivarox alloy depending upon the intended application. They contain too little of iron

Iron

Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

 and thus are not stainless steel

Stainless steel

In metallurgy, stainless steel, also known as inox steel or inox from French "inoxydable", is defined as a steel alloy with a minimum of 10.5 or 11% chromium content by mass....

 alloys per se despite the chromium percentage, but cobalt-based specialty alloys with a 42–48% concentration of cobalt

Cobalt

Cobalt is a chemical element with symbol Co and atomic number 27. It is found naturally only in chemically combined form. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal....

, other alloying elements including nickel

Nickel

Nickel is a chemical element with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile...

 (15–25%) and chromium

Chromium

Chromium is a chemical element which has the symbol Cr and atomic number 24. It is the first element in Group 6. It is a steely-gray, lustrous, hard metal that takes a high polish and has a high melting point. It is also odorless, tasteless, and malleable...

 (16–22%), along with small amounts of iron, titanium

Titanium

Titanium is a chemical element with the symbol Ti and atomic number 22. It has a low density and is a strong, lustrous, corrosion-resistant transition metal with a silver color....

 and beryllium

Beryllium

Beryllium is the chemical element with the symbol Be and atomic number 4. It is a divalent element which occurs naturally only in combination with other elements in minerals. Notable gemstones which contain beryllium include beryl and chrysoberyl...

. Hairsprings made of this alloy are wear-resistant; they are practically non-magnetic

Antimagnetic watch

Anti-magnetic watches are those that are able to run with minimal deviation when exposed to a certain magnetic field. The International Organization for Standardization issued a standard for magnetic resistant watches, which many countries have adopted.-ISO 764 magnetic resistant watches...

 and non-rusting and possess a very low coefficient of thermal expansion.

When used for critical watch components, the alloy reduces errors due to temperature variation. Along with the earlier alloy Elinvar

Elinvar

Elinvar is a nickel steel alloy with a modulus of elasticity which does not change much with temperature changes. The name is a contraction of the French elasticité invariable. It was invented in the late 1890s by Charles Édouard Guillaume, a Swiss physicist who also invented Invar, another...

, this alloy made obsolete the expensive compensation balance. Nivarox springs are now used by most watchmakers worldwide. The alloys also see limited use for specific components of sensitive scientific instruments.

Nivaflex

Nivaflex NM, NO, NE, 45/5 and 45/18 are various alloys used for the mainsprings of watches.
The NO, NM, NE, 45/5 and 45/18, are generally the same alloy (e.g. 45% Cobalt + 21% Nickel + 18% Chromium + 5% Iron + 4% Tungsten + 4% Molybdenum + 1% Titanium) except that the Nivaflex 45/5 has an additional 0.2% Beryllium.