Nivarox is an alloy of iron, nickel, chromium, titanium and beryllium used for balance springs. Nivarox springs are distinguished by their good anti-magnetic and temperature compensation features. The name is taken from the German properties of the alloy, "nicht variabel oxydfest" ("non-variable, non-oxidizing").
Nivarox was developed by Reinhard Straumann of Waldenburg in Northwest Switzerland. Although he was technical director of Thommens Uhrenfabrik at the time, Straumann developed the compound in his personal laboratory in his spare time. In 1931, he collaborated with the German materials firm Heraeus to create a new hairspring material that would not change in elasticity due to changes in ambient temperature. The resulting material, an alloy of nickel, iron, and other metals, was particularly valuable in the production of hairsprings and balance wheels. Named Nivarox, it was resistant to fracture, corrosion, and magnetism and was perfected in 1933 and patented in 1935.
Straumann left Thommen in 1934 and founded Nivarox SA in Saint-Imier that year. The company would merge with Fabriques d'Assortiments Réunies (FAR) of Le Locle in 1984 and remains one of the most valuable components of the Swatch Group.
Straumann became director of Tschudin + Heid AG, a watch component producer in Waldenburg, and continued working to create new materials in a laboratory there. He patented a new mainspring material, Nivaflex, in 1948 and founded another company in Saint-Imier to develop this material, Nivaflex SA, in 1948.
Straumann's Waldenburg research laboratory became Institute Dr. Ing. Reinhard Straumann in 1954, with research continuing on new materials. The institute focused on areas of interest to Straumann, chiefly ski flying, watch materials, and test equipment. The company would be renamed Straumann AG in 1990 and would focus on development of dental implants. Straumann's grandson founded Precision Engineering AG in 2001 to continue oversight of the Nivarox alloy, and his company merged with H. Moser & Cie. under MELB Holding in 2012.
Although Nivarox-FAR produces most balance springs used in Swiss and other European watches, a few companies produce their own springs using similar alloys. Rolex, Parmigiani, Precision Engineering AG, F. P. Journe, and A. Lange & Söhne all have the capability to produce their own Nivarox springs. Thanks to their Richemont connection with Lange, Jaeger-LeCoultre also produces springs from Lange material.
Seiko uses their own SPRON alloy for in-house spring production.