Titanium and titanium compounds


In general, titanium is treated as a kind of rare metal. However, in actual, the content of titanium in earth crust is quite high, which is richer than several common metals like zinc, bronze, and tin, even include the chlorine and phosphorus. Titanium has become a new popular material of accessories in the world. Touch with body, it has a function of promoting the blood circulation. Emit consistent wavelength, titanium can ionize cells, adjust electricity current in body, and thus bring benefits to our physiological function.

The physical property of titanium: titanium is a kind of grey metal with an atomic coefficient of 22 and a relative atomic mass of 47.87. Its metal reactivity is between that of magnesium and aluminum. At room temperature, titanium is so unstable that it can only exist in nature with a form of combination. Common titanium compounds include ilmenite, rutile, etc. Given to the content in earth crust, titanium ranks ninth on account of its richness in content. The density of pure titanium is 4.54×103kg/m3, and its molar volume is 10.54cm3/mol. With a low hardness of about 4 in Mohs’, titanium is good in ductility. Its heat stability is good too, with a melting point of 1660±10℃ and a boiling point of 3287℃.

Titanium tetrachloride is really a kind of interesting liquid. With a pungent smell, it will emit strong white smoke in moisture air, which is the symbol of its hydrolysis that makes it into white titanium dioxide hydrogel. In military, this special feature of titanium tetrachloride is taken advantage by people to produce artificial smog. Especially on the sea where is rich in moisture, titanium tetrachloride will change into a white great wall and block the view of enemies. In agriculture, titanium tetrachloride is widely used to protect plants from frost.

Barium titanate crystal has such characteristics: when it changes shape under pressure, will produce electricity, or vice versa. Thus, people put the barium titanate on the ultrasound, so as to generate a current under pressure, which can detect the intensity of ultrasonic waves by the size of current. Conversely, with a high frequency current through it, it can produce ultrasonic. Today, barium titanate is used in almost all of the ultrasonic instruments. In addition, barium titanate has many uses. For example: railway workers put it below the tracks, so as to measure the pressure when the train passed; doctors use it to make the pulse logger. The underwater detector made of barium titanate is sharp eye, which is not only able to see the fish, but also can see the underwater reefs, icebergs and enemy submarines.

Smelting titanium needs to go through many complicated steps. First, turn the ilmenite ore into titanium tetrachloride, and then put it in a sealed stainless steel tank filled with argon gas, so that they can react with magnesium, and produce “titanium sponge”. This porous “sponge titanium” cannot be used directly, you must put them in an electric furnace melted into a liquid, in order to cast titanium ingots. But manufactured this furnace was not easy at all! In addition to the furnace air must be pumped completely, the more vexing is that it is hard to find crucibles for titanium-containing liquid, because the refractory materials generally contain oxides, which will be taken from the liquid titanium. Later, it was finally invented an electric stove, “water-cooled copper crucible”. Only the central part of this furnace is hot, and the rest are cold. After the titanium is melted in an electric furnace, the flow of water met the wall of cooled copper crucible, and immediately cemented titanium ingots. In this way, it can produce several tons of titanium blocks, but the costs can be imagined.