The impossible, made possible: The lightest mechanical dive watch Diver [AIR] from Ulysse Nardin
"If it’s possible, it’s done. If it’s impossible, it will be done", said Paul-David Nardin, son of the founder of the Ulysse Nardin watch factory, in 1876. This philosophy also inspires thyssenkrupp Materials Schweiz and TiFast, the Italian titanium manufacturer, to create groundbreaking innovations. (April 2025)
"Recycling steel and aluminum is okay, but titanium? Impossible!”
That's how it sounded when the founders of TiFast decided to produce high-quality titanium alloys with a previously unprecedented recycling percentage. TiFast, near Rome, is now known as a pioneer in the sustainable production of titanium, e.g. for aviation, medical technology and motor racing. Driven by passion and conviction, the engineers at TiFast started the manufacturing process long before the words recycling and CO2 reduction dominated the headlines.
Melted under vacuum
Oxygen is destructive for titanium; depending on the alloy, the maximum percentage may be 0.40%, 0.20% or even 0.13%. Once oxygen has been dissolved in titanium, it is hard to get rid of it. Unlike other metals, titanium must therefore be melted under vacuum to avoid contact with oxygen under all circumstances. The process is energy intensive. To reduce energy and raw material costs, TiFast uses up to half titanium scrap, which is collected locally, i.e. in Switzerland and other European countries. The remainder consists of high-purity titanium sponge, which is free of oxygen. By mixing 30-50% titanium scrap with titanium sponge, it is possible to comply with the maximum limits for the oxygen content. To do this, however, you need to know what type of scrap is being delivered - i.e. each individual part is checked for its chemical composition. The surface is then cleaned of the natural oxide layer to ensure that as little oxygen as possible enters the melt.
"Recycling titanium okay, but 90%? Impossible!"
Like Ulysse Nardin, thyssenkrupp Materials Schweiz wanted to push the boundaries and increase the recycled content of titanium from 30-50% to at least 90% (hence the name ECO-90). This while complying with the standards for aviation and medical applications. Thanks to TiFast, the feat was a success. The close collaboration inspired top performance and created new manufacturing processes. As a side effect, CO2 emissions were reduced by almost half compared to traditional titanium production. This is because around 50% of CO2 emissions are generated during sponge production, with the rest coming from vacuum melting.
In order to meet the very high requirements of the watch industry and and in particular of Ulysse Nardin, the Titanium ECO-90 bars produced by TiFast were additionally subjected to the well-known HORLOBARRE process under our direction. This special treatment, developed by thyssenkrupp Materials Schweiz AG, makes titanium stress-relieved and easy to machine. This is what enables the production of extremely dimensionally stable micromechanical components. Such as those required for the lightest mechanical dive watch ever made, the Ulysse Nardin Diver [AIR]*.
Less waste, lower costs, more sustainability
HORLOBARRE ECO-90 titanium bars from thyssenkrupp Materials Schweiz AG also significantly reduce tool wear and reduce scrap, saving time and money. Less waste also means a sustainable reduction in the CO2 footprint during processing.
*World premiere presented at the Watches and Wonders 2025 in Geneva
Fiche technique Titane HORLOBARRE ECO-90
- Fiche technique Ti 6AL4V HORLOBARRE ECO-90
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