Titanium is a metal with relatively active chemical properties. It can interact with non-metals such as O2, N2, H2, S and halogen when heated. However, at normal temperature, a very thin and dense oxide protective film is easy to form on the surface of titanium, which can resist the action of strong acid and even aqua regia, showing strong corrosion resistance. Therefore, general metals become riddled in acid, alkali, and salt solutions, but titanium is safe. Liquid titanium can dissolve almost all metals, so it can form alloys with a variety of metals. Titanium steel made by adding titanium to steel is tough and elastic. Titanium and metal Al, Sb, Be, Cr, Fe, etc. form interstitial compounds or intermetallic compounds.
Aircraft made of titanium alloy can carry more than 100 passengers more than aircraft made of other metals with the same weight. The finished submarine can resist both seawater corrosion and deep pressure, and its diving depth is 80% higher than that of a stainless steel submarine. At the same time, titanium is non-magnetic and will not be found by mines, and has a good anti-monitoring effect.
Titanium is "biophilic". In the human body, it can resist the corrosion of secretions and is non-toxic, and it is suitable for any sterilization method. Therefore, it is widely used in the manufacture of medical equipment, artificial hip joints, knee joints, shoulder joints, flank joints, cranium, active heart valves, and bone fixation clips. When new muscle fiber rings wrap around these "titanium bones", these titanium bones begin to maintain the normal activities of the human body. Titanium is widely distributed in the human body, and the content in a normal human body is no more than 15 mg per 70 kg of body weight. Its role is not clear. However, titanium can stimulate phagocytes and enhance immunity. This effect has been confirmed.
Titanium compounds and uses: Important titanium compounds are: titanium dioxide (TiO2), titanium tetrachloride (TiCl4), and barium metatitanate (BaTiO3). Pure titanium dioxide is a white powder, an excellent white pigment, and the trade name is "titanium dioxide". It has both the covering properties of lead white (PbCO3) and the lasting properties of zinc white (ZnO). Therefore, people often add titanium dioxide to paint to make high-grade white paint; in the paper industry as a filler added to the paper pulp; in the textile industry as a matting agent for man-made fibers; in the glass, ceramics, and enamel industries Additives to improve its performance; used as a catalyst in many chemical reactions. With the increasing development of the chemical industry today, titanium dioxide and titanium compounds, as fine chemical products, have high added value and have very attractive prospects. Titanium tetrachloride is a colorless liquid; it has a melting point of 250K, a boiling point of 409K, and an irritating odor. It is easily hydrolyzed in water or humid air and emits a lot of white smoke. TiCl4+3H2O == H2TiO3+4HCl Therefore TiCl4 is used as an artificial aerosol in the military, but it is used in maritime warfare. In agriculture, people use the dense fog on the ground formed by TiCl4 to reduce the heat loss from the ground at night and protect vegetables and crops from severe cold and frost. The TiO2 and BaCO3 are melted together to prepare barium metatitanate: TiO2＋BaCO3 == BaTiO3 + CO2- The artificially prepared BaTiO3 has a high dielectric constant, and the capacitor made from it has a larger capacity, and more importantly, BaTiO3 has Significant "piezoelectric properties", the crystal will generate current when pressed, and will change its shape when it is energized. People put it in the ultrasonic wave, and it generates electric current when it is pressed. The strength of the ultrasonic wave can be measured by measuring the strength of the electric current. It is used in almost all ultrasonic instruments. With the development and utilization of titanate, it is more and more widely used to manufacture non-linear components, dielectric amplifiers, computer memory components, miniature capacitors, electroplating materials, aviation materials, strong magnetism, semiconductor materials, optical instruments, reagents, etc. . The excellent properties of titanium, titanium alloys and titanium compounds prompt humans to urgently need them. However, the high production cost limits the application. We believe that in the near future, with the continuous improvement and improvement of titanium smelting technology, the application of titanium, titanium alloys and titanium compounds will be further developed.
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