The Application of Titanium in Watches

Watches are essential items in people's daily lives, and the cases and bands of watches account for 95% of the materials used in watches. Traditionally, watches were made of brass and electroplated with Ni on the surface. Such watches contain a large amount of nickel in the surface layer, which often causes "nickel allergy" when worn. Later, watches made of austenitic stainless steel appeared, but since austenitic stainless steel also contains nickel and chromium and other elements that can cause allergic reactions with human skin, since the 1970s, relevant scientific and technological personnel have begun to study the use of titanium materials with good compatibility with the human body to manufacture watch cases, bands, straps, buckles, and lugs.

The use of titanium as a watch material began with high-end waterproof sports watches with chronograph functions. The development of titanium watches in Japan was initiated by two major manufacturers, Citizen and Seiko, simultaneously launching high-end titanium sports watches. Subsequently, Japanese watch companies began to research all-titanium watches in 1972. To apply titanium to watches, researchers have solved seven major technical problems over nearly 30 years, including pressure forming technology, cutting processing technology, surface processing technology, wear-resistant treatment process, weldability, decorative properties, and biocompatibility.

Therefore, modern titanium watches have the following characteristics: light weight, 60% of that of stainless steel; resistant to corrosion by human sweat and seawater; having the best specific strength among metal materials; surface hardness twice that of stainless steel; no cold feeling when worn like other metals; good compatibility with skin and no allergic reactions; good decorative effect, etc.

Currently, the titanium materials used in watchmaking include industrial pure titanium, Ti-6Al-4V, and titanium alloy Ti-15333. In the early 1990s, the first all-titanium watches entered the market at extremely high prices. Subsequently, due to increased production and technological improvements, watch cases can be manufactured using investment casting, sheet metal stamping, and powder metallurgy methods, and the prices have decreased accordingly. All-titanium watches have shifted from high-end to mass-market products.

Many countries around the world attach great importance to the research and production of titanium watches. The research work on titanium watches in Japan won the Merit Award of the Japan Titanium Association in 1994. The titanium metal space watch produced in Switzerland weighs only 50g. The Northwest Institute for Nonferrous Metal Research in China has also developed a series of all-titanium watches under the brand name "NIN".

With the development of 3D printing technology, personalized custom-printed titanium watches are constantly emerging. The Luminor 1950 case is made of titanium metal, is anti-sensitive and anti-corrosive, and is 40% lighter than steel. To further reduce the weight of the watch, the case is hollowed out with an innovative technology, outlining extremely complex geometric shapes while maintaining excellent water resistance (up to 10 bar, approximately 100 meters depth) and the strength to resist tension and torsion. This technology is called "direct metal laser sintering", which uses titanium metal powder to construct three-dimensional parts layer by layer with fiber laser technology, with each layer being only 0.02 mm thick. After fusion, it becomes solid titanium metal. The finished product is not made with traditional techniques, is lighter, and has a uniform and flawless appearance.