Everyone we work in now has a preliminary understanding of titanium. We all know that titanium is a kind of light weight, corrosion resistance, good heat resistance and many other excellent properties, known as "future metal" "21 "Century Metal" is a new type of structural material with a promising future. It is a kind of aluminum metal color, everyone also understand some of the relevant knowledge of titanium. Let’s start with sponge titanium. China’s titanium ore reserves are about 64% of the world’s proven reserves. From the perspective of the type of ore industry, China’s titanium resources are mainly primary vanadium-titanium magnetite rock ore, followed by exogenous titanium Iron ore sand mines, the third is rutile rock mines, and the fourth is rutile sand mines, as long as China's titanium concentrate production capacity is distributed in Panzhihua, Sichuan, Hainan, Guangxi, Panzhihua is China's largest titanium concentrate supply base, accounting for 90% of the Chinese market %the above. Titanium resources are mainly used to produce titanium white, metal titanium (sponge titanium), titanium-containing steel and titanium welding wire and coatings. Sponge titanium is mainly through the two methods of magnesium reduction and sodium reduction (distillation method). Other methods have not been industrially produced. At the end of 2008, China's sponge titanium production reached 60,000 tons, ranking first in the world. Titanium processed materials are around 27,000 tons, and Baotai Titanium processed titanium materials were 11,000 tons in 2008. Titanium ingot production is about 50,000 tons. Bao Ti only accounts for more than 1/5. Titanium is the largest in chemical industry in China, accounting for about 44% of the national titanium consumption, aerospace accounting for about 17%, and sports and leisure use of titanium is 16%, ranking third. (According to statistics in 2007). In the United States and Europe, titanium materials are mainly used in the aerospace field, accounting for about 60%, and in Japan, titanium materials are mainly used in the fields of chemical industry and electric power, accounting for about 50%. In China, it is mainly used in chemical industry, sports and other fields, accounting for about 70%. The major foreign titanium production enterprises include American Titanium Metal, Timet, RTI International Metals Corporation, Allegheny, Kobe Steel of Japan, Sumitomo Titanium and Nippon Steel. VSMPO-AVISMA of Russia.
How is the titanium rod processed? When we were not in contact with titanium before, we all had a mysterious feeling about titanium. Indeed, titanium is an emerging metal. In the 20th century, when we talked about titanium, many people, young and old, would feel strange to us, not to mention the whole country. Even our Baoji is known as China’s titanium city, and not many people know about titanium. Therefore, titanium is called a rare metal. Among the once rare rare earth groups in China, there are Bao Titanium Group and Zunyi Titanium Industry. In fact, titanium is not a scarce element on the earth, and it ranks tenth among all elements. Discharging it into rare metals is mainly due to difficulties in smelting and complicated processes, resulting in high production costs, so the market price is high. The price of titanium is about ten times that of stainless steel and about 100 times that of ordinary steel. General places are unavailable, and so far they have only been used in places where space, aviation, military, chemical, medical, etc. are affordable or indispensable. The Chinese civilian market was only widely promoted and applied in the mid-1970s. Now that titanium is becoming more widely used and the production capacity of titanium has increased substantially year by year, more and more people know and understand titanium. Now the application of titanium in addition to aircraft, rockets, missiles, submarines in the defense industry, chemical, medical, sports, automotive, construction, daily life have titanium and titanium alloy applications. And in the future, this piece of titanium will grow bigger and bigger, develop faster and faster, and be used more and more widely. Titanium is a sunrise industry. Therefore, all of us should have full confidence in the future of our enterprise.
Why talk about the application of titanium today? The reason is that we work in the titanium industry every day, we should know where our products are used, otherwise, relatives and friends ask you what titanium is used for, and where , It would be embarrassing not to answer. The people in the sales department know where to go to find the market, and the people in the quality department know this, and they know why the standards for titanium materials are so required. Titanium was discovered by British analytical chemist Gregor in the Monachen Valley of England in 1789. Although he was extremely interested, it did not attract people's attention. It was not developed until the 1940s and 50s. The application of titanium has only a history of more than 50 years. At the beginning, it was the first time the American made a titanium alloy in 1954, that is, Ti-6AI-4V. The earliest application of titanium was from the aviation industry. Later, in the development of rockets, missiles, artificial satellites, and aerospace equipment, many advantages of titanium were considered, and it has also become one of the important materials used in these fields. Until now, it has been widely used in civil and daily products. All over the industry. Here are 12 aspects:
1. Aviation field
The largest user of titanium materials in the past and now is the aviation industry, and now titanium and titanium alloy materials are widely used in military and civilian aircraft, and the amount directly affects the rise and decline of the titanium industry. If the world economy enters a recession, it will directly react In the world's aviation industry, fewer people travel by air, and the aviation industry in various countries is sluggish. Aircraft orders will be less, and the amount of titanium used will be less. After the 9.11 incident in the United States in 2001, there was a short period of low tide in the world aviation industry, and short-term adjustments occurred. As a result, the titanium industry also shrank for a period of time. During the slow recession period, the world economy has also been affected to a certain extent, but at present it is not obvious how much impact it has on the titanium industry. The application of titanium in aircraft mainly includes the following places.
(1) It is an engine. The amount of titanium used in each engine accounts for 20 to 30% of the total weight of the engine. It is mainly the components of the compressor, including blades, hubs, inlet guide valves and shells.
(2) It is an aircraft skeleton, and the amount of titanium used in this respect is also very large, because the specific strength of titanium alloy is high, making titanium is the first choice among all metal materials, everyone knows that our country also wants to manufacture large aircraft, one of which is very important The hardware is a large-tonnage forging machine. At present, the world’s largest titanium alloy die forging machine is 75,000 tons in Russia. Now it has been established in Yanliang, Xi’an, and is preparing a die forging machine with 80,000 tons. The first phase For the project of 40,000 tons, the investment is 195 million yuan. It will be put into production at the end of 2009. For the second stage project, 80,000 tons, the investment is 850 million yuan. What is the material forged by these die forging machines is the aircraft skeleton of titanium alloy material. Especially the middle and rear sections of the rack. The middle section is the connecting section of the wing and the fuselage, which is the most stressed part of the frame, and the rear part is the engine installation part, which is also an important part of the force.
(3) Landing gear, support frame, etc. Many aircraft crashes are at the time of landing, because the aircraft has a large load and impact force when landing, so the requirements for the landing gear are very high. Choosing titanium alloy not only guarantees high-strength impact resistance performance requirements, but also lighter weight than choosing high-quality steel.
(4) Riveted parts for wing skins and internal fixation. Some aircraft choose titanium materials for wing skins. They are mainly military aircraft. There are tens of thousands of rivets and fasteners on an aircraft. Our country produces cold There are three or four professional standard parts factories for hot rivets and fasteners. Their factories only produce various types of bolts, nuts, rivets, and most of them are made of titanium and titanium alloy materials. .
So how much titanium does an aircraft use? As an example, everyone has heard of the Boeing 747 aircraft in the United States. One aircraft uses 35 tons of titanium. Russia's Su-27ck uses 8 tons of titanium, the United States' early F-15 uses 7 tons of titanium, accounting for 25% of its total body weight, and the later F-15 uses titanium to increase to 8 tons. 4, US F/A —22 is the world’s fourth-generation fighter in the true sense. By July 2007, 100 aircraft have been delivered. This type is the most used titanium alloy and composite material in American fighters. One F/A -22 The body of titanium alloy uses an astonishing 36 tons of blanks. The processed titanium parts account for 41% of the aircraft's total weight. There are no statistics on the number of military and civil aircraft in the world, but we can know from this that the aviation industry is a big buyer of the titanium industry. Therefore, the aviation industry is booming, so is the titanium industry. Many foreign companies choose Chinese titanium products because of our price advantage.
2. Aerospace field
Titanium and titanium alloys can be used in high-pressure vessels, fuel storage tanks, rocket engines and missile shells in the rocket, missile and spacecraft industries. Spaceship cabin skin and structural skeleton. Main landing gear. Moon landing cabin, etc.
At present, the world's titanium used for space navigation has reached more than 1,000 tons. The amount of titanium used in aerospace products is close to that of aviation. The United States Space Shuttle uses more titanium than ordinary military and civilian aircraft. The fuselage of the American Columbia Space Shuttle. The engine bracket and the compressor of the engine. The vertical tail. The elevator auxiliary wings are all made of titanium. Made. Each country launches many rockets every year to send various artificial satellites to the sky. The rocket's engine is not as big as an aircraft. The engine's compressor is also a large selection of titanium materials. According to reports, titanium materials are also widely used on the International Space Station abroad. The cockpit of the "Mercury" spacecraft uses 168 kg of titanium, accounting for 80% of its total weight. The "Apollo" spacecraft is in the bracket. Fastening body. Fixture. Mechanical cabin. Lunar cabin. Hydraulic tank and other devices use a total of 1180Kg of titanium There are many types and large numbers of missiles all over the world. Whether it is a general missile or an intercontinental missile, every missile has an engine regardless of its size. Its blades and engine fuselage are made of titanium, and its fuel oxidizer tank is also They are all made of titanium, and we can only estimate how much titanium material will be used, because that country will not announce how many missiles it has.
3. Other military fields
In the corrosive environment of the ocean, titanium materials are widely used in warships and submarines, such as the pressure shell of the submarine. Rudder, shaft bracket, ball valve. Fire extinguishing pump. Heat exchanger. Cooler, sonar diversion of the hull Hood, propeller and propeller shaft of the waterjet propulsion system of the power plant, ship piping system, casting, etc. In addition to weapon systems, many places are made of titanium. According to reports, an all-titanium submarine produced in Russia, each of which uses 3,000 to 3,500 tons of titanium, can double the diving depth. Can sail in the deep sea up to 4500 meters. At the same time, due to the decrease in total weight, the speed is greatly increased. Some equipment on other ships such as condensers, steam generators, valves, large flanges, torpedo launchers, whip antennas, pump bodies, etc. are all made of titanium materials. In addition, some materials such as gun barrels, armored vehicles, engineering equipment, new tanks, etc. also use titanium materials. For example, the base of the current mortar is titanium alloy.
4. Chemical system
In industries such as petrochemicals, chemical fertilizers, acids and alkalis, sodium, chlorine and seawater desalination, titanium and titanium alloys can be used as heat exchangers, reaction towers, distillers, washing towers, synthesizers, autoclaves, valves, and conduits. Pumps, pipes, etc.
In terms of usage, the chemical system is a major user of the titanium industry in civil use. In 2007, the output value of 10 large-scale titanium equipment companies in the country reached 1.361181 billion yuan. Due to the many acids and alkalis in titanium and titanium alloys, Salt media has excellent corrosion resistance, at the same time has the advantages of light weight and high specific strength, so it is widely used in chemical, petroleum, marine engineering and other fields. Although the cost of using titanium is higher, it is still cost-effective to use titanium in terms of comprehensive life cycle, strength, and environmental impact, and it can obtain significant economic benefits. There are five main aspects in the chemical industry:
(1) Soda ash industry
Soda ash, whose scientific name is sodium carbonate, is one of the basic chemical raw materials and is in great demand. The equipment using the ammonia-alkali method or the combined alkali-making method will be strongly corroded by media such as sodium chloride and ammonium chloride. If you use steel or stainless steel, you must frequently replace the equipment, often stop production and maintenance, and the loss is very large, while using titanium for 5 years The above is intact, this titanium material is very valuable. In the past, the external cooler used to cool the crystalline ammonium chloride mother liquor in the soda ash industry used carbon steel materials, with a life of only 1 to 4 years, while the annual corrosion rate of titanium materials is only 0.001mm/year. Can be used for at least several decades.
(2) Chlor-alkali industry
The chlor-alkali industry is to produce sodium hydroxide and chlorine products, such as hydrochloric acid and sodium hypochlorite, by using the salt we eat through electrolysis. Sodium hydroxide is the main raw material in the paper industry, and sodium hypochlorite is widely used in disinfection. In the past, graphite electrodes have been used as insoluble anodes for electrolysis, and many problems have occurred in actual production. For example, because graphite is not resistant to high temperatures and salt water corrosion, its service life is generally only 4 to 9 months. Corrosion causes the pole distance to increase gradually, and the power consumption also increases. In addition, because the graphite is corroded off and enters the lye, the quality of the lye is reduced. After being replaced with titanium anode, it is resistant to high temperature salt water corrosion, has excellent electrical conductivity, very little change in pole distance, stable tank voltage, and anode service life can reach more than 10 years. And the quality of lye has been significantly improved. The comprehensive benefits have been greatly improved. (Titanium anode is to insert a pure copper rod as large as the inner diameter into the titanium tube, and then processed into various shapes by rolling, cut to a certain length, and then seal the end with titanium.) So here Titanium anodes are widely used in the industry.
(3) Bleaching powder industry
Bleach powder is one of the chlorine products. Bleach powder is widely used in the textile printing and dyeing industry. The equipment for the production of bleaching powder is exposed to strong corrosive media such as wet chlorine, hypochlorite, etc., so the corrosion problem is very serious. The equipment maintenance workload is very large, and the production is often shut down for maintenance. The operating rate of general enterprises is very low, especially the cross arm of the reaction tower And the scraper, the corrosion is very serious.
After using the titanium cross arm and the titanium scraper, the operation is good, the effect is very significant, and a good economic benefit is achieved. The cost of maintenance and replacement of equipment is greatly reduced, and the output of bleaching powder is significantly increased.
(4) Urea industry
Urea is one of the main chemical fertilizers and is a high-quality and efficient nitrogen fertilizer. In recent years, the scale of urea production at home and abroad is very large, and the corrosion problems of urea synthesis towers are very large. In the past, the use of stainless steel materials to manufacture synthesis towers has local corrosion problems, and the use temperature is limited to 190 ℃. The corrosion rate will exceed this temperature. Increase, which limits the temperature of synthetic urea. The conversion rate of urea is very low. The use of pure titanium lined urea synthesis tower not only solves the corrosion problem, but also improves the conversion rate of synthetic urea. In the equipment for urea production, the stripping tower, decomposition system, reciprocating high-pressure methyl ammonium pump, pressure reducing valve, etc. are now made of titanium.
(5) Other chemicals
In the chemical industry, there are many varieties such as lactam, maleic anhydride, propylene, acetone, terephthalic acid, acetaldehyde, etc., and titanium is widely used in production equipment, mainly in titanium plate and titanium tube production equipment. Reactor, and connecting pipes. And the service life of the reaction kettle is constant, and the replacement is also very frequent. Some reactors are very large, and each weighs a few tons or tens of tons. In addition, they are dealing with corrosive substances such as nitric acid, organic acids and hydrochloric acid. . Hydrogen sulfide also uses a large number of titanium containers. Heat exchangers. Tanks. Stirrers. Coolers and piping systems, so there are many pressure vessel manufacturers in the titanium industry in the country, which consumes a large amount of titanium plates and titanium tubes every year. .
5. Application of titanium equipment in petroleum industry
Petroleum produces gasoline, diesel, kerosene and other products through refining, but crude oil contains sulfides and chlorides, which are very corrosive to equipment, especially petroleum refining equipment such as primary distillation tower, atmospheric pressure tower top, and tower top condenser are made of titanium The above-mentioned equipment manufactured has achieved good results and basically solved the corrosion problem of the equipment.
In refineries, titanium equipment is widely used in processes such as catalytic cracking, process water treatment, hydrotreating, desulfurization, unsaturated separation, hydrogen purification, reforming, tubular distillation, and polymerization.
6. Application of titanium equipment in metallurgical industry
With the rapid development of the metallurgical industry, titanium has been promoted and applied as a structural material with high strength and corrosion resistance. In the hydrometallurgical process, because the equipment is exposed to alkali, acid and various corrosive gases, soot, traditional aluminum alloys, acid-resistant stainless steel and other materials, it cannot meet the needs of the production process, which limits the development of hydrometallurgy. The use of titanium equipment is of great significance for improving production efficiency, solving the common problems of hydrometallurgy, running drip, and reducing environmental pollution.
(1) The application of titanium equipment in the production of electrolytic nickel
In the production of electrolytic nickel, equipment is exposed to highly acidic solutions and active ions, and titanium has excellent corrosion resistance, making it an ideal material for manufacturing electrolytic nickel equipment.
Compared with stainless steel motherboards, the cathode motherboard in electrolytic nickel production has better economic effect and superior performance. For example, the deposited nickel skin is not easy to stain the board, the peeling is easy, the peeling rate is improved, and the starting plate of the titanium master is flat , Good rigidity, uniform current density during electrolysis, etc. In addition, heaters, pumps, valves, etc. in electrolytic nickel production equipment also use a large amount of titanium materials.
(2) The application of titanium equipment in the production of electrolytic copper
The cathode rolls of electrolytic copper production equipment were originally made of steel cathode rolls. Due to the corrosion of the electrolyte, pitting corrosion occurred on the surface of the rolls, which affected the quality of the copper foil, and regular grinding of the rolls wasted human and financial resources. The use of titanium rollers solved these problems. In addition, most of the heaters and cathode motherboards in the production of electrolytic copper are made of titanium.
(3) Hydrometallurgy of other metals
Titanium equipment is also used for smelting of cobalt, zinc, aluminum, mercury, etc., purification of tungstic acid, etc. The main equipment in the metallurgical industry are electrolytic cells, reactors, scrubbers, heat exchangers, agitators, evaporation devices, dust collection devices, etc. , Have achieved significant benefits. There are also foreign countries that use titanium pumps to transport chloride, sodium chloride, potassium chloride, and dilute hydrochloric acid. The life of the pump is 5-20 times longer than that of a cast iron pump or stainless steel pump, and the liquid loss is reduced by three-fifths. The tank can be used for 3-4 years, while the steel storage tank can only be used for 2 months.
7. Application of titanium equipment in the power industry
The condensers of thermal power stations and nuclear power plants are important equipment for generating sets, mainly in the coastal power industry. These enterprises use seawater to cool condensate, which contains a large amount of sediment, suspended matter, sea creatures, and various Corrosive substances are even more severe in fresh salt water with alternating seawater and river water. Conventional condensers use copper alloy tubes. The corrosion rate of copper alloy tubes in the seawater environment is very high, and they are often severely damaged. The condenser will corrode and leak after operating for about one year. As early as the 1970s, China began the research on titanium tubes for power plant condensers. Baotai Group undertaken the development task of cold-rolled thin-walled seamless titanium tubes. The titanium tubes provided in Jinshan Thermal Power Plant, Zhenhai Power Plant, etc. After being used in the device, it has achieved significant economic benefits. The life of the titanium tube is 4-6 times longer than that of the copper tube in this same environment, ensuring stable and safe production of the power plant.
8. Application of titanium equipment in marine engineering
At present, titanium for marine engineering has become an important field of titanium products for civilian use.
(1) Offshore oil and gas development
Offshore oil extraction equipment mainly includes oil production platforms and ancillary equipment. The ancillary equipment includes crude oil coolers, oil risers, pumps, valves, joints and fixtures. These devices are in contact with sulfide, ammonia, chlorine and other media in seawater and crude oil. Because titanium has excellent corrosion resistance in these media, the United States used offshore oil platform props made of titanium in its oil fields as early as the 1970s, and at the same time used titanium to manufacture tube heat exchangers and plate heat exchangers. . The United States uses 100 titanium heat exchangers on the North Sea oil field drilling platform.
Titanium drilling pipe has a long service life, its weight is only half of stainless steel, but the use flexibility is twice that of stainless steel, and the service life is 10 times that of stainless steel. In 2000, several companies in the United States put titanium drilling tubes Used in offshore oil production.
(2) Seawater desalination
Early seawater desalination devices used copper alloys, carbon steel, and other materials. Because these materials are not resistant to seawater corrosion, the production efficiency is low, and they are quickly replaced by titanium materials with excellent seawater corrosion resistance. In the desalination of seawater, the main application of titanium is the heat transfer tube of the desalination device. A Japanese company built 10 distillation devices for Saudi Arabia with a daily output of 30,000 tons of fresh water, using 3,200 tons of titanium tubes. 107 tons of titanium, the amount of titanium used in seawater desalination projects in Tianjin, Shandong and other places in China is about 250 tons.
(3) Shipbuilding industry
Titanium and titanium alloys are widely used in ships, such as hull structural parts, deep-sea survey ships and ocean thermal energy conversion, and marine fisheries. For example, in the coastal areas, titanium metal nets are used for artificial breeding, the titanium metal nets are basically not corroded at sea, and they have not been replaced for many years. A heat exchanger made of titanium tubes heats the seawater to ensure the temperature required for the fish being reared. In the field of ocean thermal energy conversion, titanium equipment is used in the main equipment evaporators, condensers, seawater suction pipes, and loop systems of thermoelectric power plants in the United States and Japan, all of which have achieved good results.
9. Medical applications
The application of titanium in medicine has two main aspects: pharmaceuticals and human implants.
(1) Application of titanium equipment in the pharmaceutical industry
In the pharmaceutical production process, the equipment is exposed to media such as hydrochloric acid, nitric acid, acetic acid, sulfuric acid and its salts and organic solvents, and the equipment is very corroded. If the production and maintenance are often stopped, it will affect the production, and the corrosion of the equipment will directly affect the quality of the medicine. Therefore, many pharmaceutical companies now use titanium materials for the airflow drying devices, pipelines, spiral feeders, heaters, and cyclones in pharmaceutical equipment. On the one hand, the corrosion rate is only 0.008-0.003mm/a, the most important thing is Ensure that the quality of the medicine will not be affected by the corrosion of the equipment.
(2) Application of titanium materials in human body
Because titanium has higher strength, lower modulus, and good biocompatibility, it has now become a commonly used substitute for human bones in medicine. Titanium is used to make hip joints, elbow joints, bone screws, knee joints, and bone plates. .Dental implants (that is, dental implants in dental hospitals, the price is very high), denture brackets, crowns and bridges, and orthodontic filaments, surgical instruments, heart rate regulator boxes, etc. Even now it has developed into titanium alloy precision casting prosthesis. Some children's teeth are not straight and need to be corrected. The stomatological hospital will use a memory alloy wire made of titanium-nickel alloy for correction. Some people have narrow blood vessels in a certain part. The doctor will recommend implanting a blood vessel made of titanium material. The stent can now be replaced with titanium materials from head to toe. There is a 68-year-old Peter Houghton in the United States with a serious heart disease. The doctor installed a titanium device in his heart to save his life. To help his heart pump blood, he lived on this device for another seven and a half years, becoming the longest person to live on an artificial heart. However, medical titanium materials are the most stringent and discerning in terms of quality requirements, especially the metallographic requirements can be said to be the most stringent, which is higher than military requirements. There can be no segregation at low magnification, and the organization of high magnification needs to be very uniform.
10. Sports goods
We saw some high-income people playing golf on TV. The head of the club is made of titanium alloy. Our nearby titanium factory is specializing in the production of golf clubs. It is produced by casting method. There are also all-titanium bikes, titanium badminton rackets, tennis rackets, saddles for horse race riders, etc.
11. Automobile manufacturing industry
Because titanium is a light-weight, high-strength, high-elasticity, and good corrosion-resistant material, it can be used in automobiles to reduce weight, save energy, reduce shock, reduce noise, reduce pollution, and extend life to improve vehicle safety and comfort. It is an ideal material for realizing the lightweight of automobiles. However, due to the high price of titanium materials, it cannot be widely used in ordinary cars. It is only used in high-end cars and racing cars. The currently recognized parts that can be replaced by titanium in automobiles are mainly Springs, connecting rods, valves, valve seats, rocker arms, exhaust pipes, silencers, door frames, front bezels, tailgates, doors, door side covers, fasteners, ear nuts, wheels, etc. The United States and Japan have successively used titanium materials in cars. As early as 1956, the United States manufactured the "Firebird 2" all-titanium car. Japan’s Mitsubishi and Honda have successively applied titanium materials to replace steel materials in some high-end cars and racing cars. In 2006, Audi USA launched the titanium 2006 Audi.
12. Other fields
Recently, a motorcycle company in the United States launched a high-end motorcycle with an all-titanium frame and an all-titanium exhaust cylinder. The body weight is 199.5 kg, and the engine is a V2 type. There are only ten global models limited to each, and the price is $275,000. The jewelry worn by women in the Americas includes COI titanium bracelets, titanium rings, titanium earrings, titanium pendants, and titanium diamond rings. Now the domestically produced titanium jewelry is also quite exquisite. Titanium is not used too much in culture, but titanium is used in the shell of some high-end products such as digital cameras and notebook computers. In addition, many titanium materials have been used on the roof of the building. Apart from Japan, China has set a precedent in the National Grand Theater. In addition, there are a lot of new things in daily use, including titanium crutches, titanium tea boxes, titanium tableware, and watches made of titanium shells. Yang Liwei on the Chinese Shenwu spaceship is wearing a titanium alloy watch and traveling in space for 21 hours 23 minute. The two astronauts on Shenzhou VI wore a watch made of titanium with a weight of only 94 grams, which greatly improved the surface hardness and corrosion resistance, and rose to a new height than the titanium alloy watch. This process has not been reported, but it is likely to use ion nitridation.