Application of titanium and titanium alloys in spectacle frames and watches

Various titanium spectacle frames matured abroad and began mass production in the early 1990s. Before 1998, titanium spectacle frames accounted for more than 60% of the Japanese market. Titanium spectacle frames are mid-to-high-end consumer goods. In recent years, with the improvement of our people's living standards, the domestic demand for titanium spectacle frames has rapidly expanded, and there have also been many manufacturers of titanium spectacle frames in China.

　　 Titanium for spectacle frames currently uses pure titanium, Ti-Ni alloy and p-titanium alloy. Its advantages are corrosion resistance, light weight, super elasticity, and non-discoloration, which are well received by consumers. The world’s first titanium spectacle frame was developed by Nihon Kogyo Co., Ltd., overcoming the difficulties in titanium processing. Since 1981, it has been sold under the names of titanium spectacles "TitexA" and "TitexB", using titanium "TitexA" The above has solved the problems of mold breakage during drawing and stamping, and the surface finish of the machined surface, and the best cutting conditions for the machined surface have been obtained for cutting. Regarding surface processing, focus on solving abrasives, polishing rolls, processing machinery, processing conditions, etc. Regarding brazing, which is the biggest obstacle, breakthroughs have been made in the development of new titanium solders. The final surface treatment problem is that it is difficult to treat titanium with the previous wet electroplating of precious metals on the material (zinc-nickel alloy, nickel alloy, stainless steel, etc.), so ion plating is used. Nitriding can get golden yellow, and chromium nitride can get silver-white titanium coating. In addition, these nitrides are super hard materials, giving the surface good wear resistance. In addition, spray paint can also be used to obtain brownish yellow.

The weight of the TitexA sample is about 16g. TitexB uses titanium as the core material and coats the surface with a corrosion-resistant metal material. The weight of the TitexB sample is about 17g, which is about 30% lighter than the previous materials. Malmaoptica丨The company sells titanium frame Marman "fitanos" in two styles, the frame weighs about 13g.

　　 Watches are necessities in people's daily life. Traditional watches whose case and bracelet account for the watch materials are made of brass and the surface is electroplated with Ni. The surface layer of this watch contains a large amount of nickel, which often causes "nickel allergic reaction" when worn. Later, watches made of austenitic stainless steel appeared, but austenitic stainless steel also contains elements such as nickel and chromium that can cause allergic reactions with human skin. Therefore, since the TOs of the 20th century, relevant scientific and technical personnel have studied the use of titanium materials that are compatible with the human body to make watch cases, bracelets, straps, clasps and other parts. Titanium, as a watch material, started from high-end waterproof sports watches with timing functions. There are two major manufacturers of titanium watches in Japan, namely Citizen and Seiko, and they also put high-end titanium sports watches into the market. The Japanese Watch Company began to develop all-titanium watches in 1972. In order to apply titanium to watches, in the course of nearly 30 years of research, researchers have solved 7 major technical problems: ①pressure forming technology; ②cutting processing technology; ③surface processing technology; ④wear-resistant treatment technology; ⑤weldability ⑥Decorative; ⑦Biological adaptability. Modern titanium watches have the following characteristics: light weight, 60% of stainless steel; resistant to human sweat and seawater; it has the best specific strength among metal materials; surface hardness is twice that of stainless steel; there is no general metal cold when worn The feeling; good affinity with the skin, no allergic reaction; good decorative effect. The titanium materials used are industrial pure titanium; Ti-6A1-4V and titanium alloy Ti-15-3-3-3.