Titanium was originally named "gregorite" by the British chemist Reverend William Gregor, who discovered it in 1791. Titanium was then independently discovered by the German chemist M. H. Klaproth in 1793. He named him a titan in honor of the titans from Greek mythology - "the embodiment of natural strength." It was not until 1797 that Klaproth discovered that his titanium was an element previously discovered by Gregor.

Characteristics and properties

Titanium is a chemical element with the symbol Ti and atomic number 22. It is a shiny metal with a silvery color, low density, and high strength. It is resistant to corrosion in sea water and chlorine.

Element meets in a number of mineral deposits, mainly rutile and ilmenite, which are widely distributed in the earth's crust and lithosphere.

Titanium is used to produce strong light alloys. The two most useful properties of a metal are corrosion resistance and a hardness to density ratio, the highest of any metallic element. In its unalloyed state, this metal is as strong as some steels, but less dense.

Physical properties of metal

It's a strong metal with low density, rather ductile (especially in anoxic environment), brilliant and metalloid white. Its relatively high melting point of over 1650°C (or 3000°F) makes it useful as a refractory metal. It is paramagnetic and has rather low electrical and thermal conductivity.

On the Mohs scale, the hardness of titanium is 6. According to this indicator, it is slightly inferior to hardened steel and tungsten.

Commercially pure (99.2%) titanium has a tensile strength of about 434 MPa, which is in line with conventional low grade steel alloys, but titanium is much lighter.

Chemical properties of titanium

Like aluminum and magnesium, titanium and its alloys oxidize immediately when exposed to air. It reacts slowly with water and air at temperatures environment, because it forms a passive oxide coating which protects bulk metal from further oxidation.

Atmospheric passivation gives titanium excellent corrosion resistance almost equivalent to platinum. Titanium is able to withstand the attack of dilute sulfuric and hydrochloric acids, chloride solutions and most organic acids.

Titanium is one of the few elements that burns in pure nitrogen, reacting at 800° C (1470° F) to form titanium nitride. Due to their high reactivity with oxygen, nitrogen and some other gases, titanium filaments are used in titanium sublimation pumps as absorbers for these gases. These pumps are inexpensive and reliably produce extremely low pressures in UHV systems.

Common titanium-bearing minerals are anatase, brookite, ilmenite, perovskite, rutile, and titanite (sphene). Of these minerals, only rutile and ilmenite have economic importance, but even these are difficult to find in high concentrations.

Titanium is found in meteorites and has been found in the Sun and M-type stars with a surface temperature of 3200° C (5790° F).

Currently known methods for extracting titanium from various ores are labor intensive and expensive.

Production and manufacturing

Currently, about 50 grades of titanium and titanium alloys have been developed and are being used. To date, 31 classes of titanium metal and alloys are recognized, of which classes 1-4 are commercially pure (unalloyed). They differ in tensile strength depending on the oxygen content, with Grade 1 being the most ductile (lowest tensile strength with 0.18% oxygen) and Grade 4 being the least ductile (maximum tensile strength with 0.40% oxygen). ).

The remaining classes are alloys, each of which has specific properties:

• plastic;
• strength;
• hardness;
• electrical resistance;
• specific corrosion resistance and their combinations.

In addition to these specifications, titanium alloys are also manufactured to meet aerospace and military equipment(SAE-AMS, MIL-T), ISO standards and country specific specifications as well as end user requirements for aerospace, military, medical and industrial applications.

A commercially clean flat product (sheet, plate) can be easily formed, but processing must take into account the fact that the metal has a "memory" and a tendency to return back. This is especially true for some high-strength alloys.

Titanium is often used to make alloys:

• with aluminum;
• with vanadium;
• with copper (for hardening);
• with iron;
• with manganese;
• with molybdenum and other metals.

Areas of use

Titanium alloys in the form of sheet, plate, rod, wire, casting find applications in industrial, aerospace, recreational and emerging markets. Powdered titanium is used in pyrotechnics as a source of bright burning particles.

Because titanium alloys have a high tensile strength to density ratio, high corrosion resistance, fatigue resistance, high crack resistance, and ability to withstand moderately high temperatures, they are used in aircraft, armor, ships, spacecraft, and rockets.

For these applications, titanium is alloyed with aluminium, zirconium, nickel, vanadium and other elements to produce a variety of components including critical structural members, fire walls, landing gear, exhaust pipes (helicopters) and hydraulic systems. In fact, about two-thirds of the titanium metal produced is used in aircraft engines and frames.

Since titanium alloys are resistant to seawater corrosion, they are used to make propeller shafts, heat exchanger fittings, etc. These alloys are used in housings and components of ocean observation and monitoring devices for science and the military.

Specific alloys are used in downhole and oil wells and nickel hydrometallurgy for their high strength. The pulp and paper industry uses titanium in technological equipment exposed to aggressive media such as sodium hypochlorite or wet chlorine gas (in bleaching). Other applications include ultrasonic welding, wave soldering.

In addition, these alloys are used in automobiles, especially in automobile and motorcycle racing, where low weight, high strength and stiffness are essential.

Titanium is used in many sporting goods: tennis rackets, golf clubs, lacrosse rollers; cricket, hockey, lacrosse and football helmets, as well as bicycle frames and components.

Due to its durability, titanium has become more popular for design jewelry(in particular, titanium rings). Its inertness makes it a good choice for people with allergies or those who will be wearing jewelry in environments such as swimming pools. Titanium is also alloyed with gold to produce an alloy that can be sold as 24 carat gold because 1% alloyed Ti is not enough to require a lower grade. The resulting alloy is about the hardness of 14 carat gold and is stronger than pure 24 carat gold.

Precautionary measures

Titanium is non-toxic even in high doses. In powder form or as metal shavings, it poses a serious fire hazard and, if heated in air, an explosion hazard.

Properties and Applications of Titanium Alloys

Below is an overview of the most commonly encountered titanium alloys, which are divided into classes, their properties, advantages and industrial applications.

7th grade

Grade 7 is mechanically and physically equivalent to Grade 2 pure titanium, except for the addition of an intermediate element of palladium, making it an alloy. It has excellent weldability and elasticity, the most corrosion resistance of all alloys of this type.

Class 7 is used in chemical processes and manufacturing equipment components.

Grade 11

Grade 11 is very similar to Grade 1, except for the addition of palladium to improve corrosion resistance, making it an alloy.

Other useful properties include optimum ductility, strength, toughness and excellent weldability. This alloy can be used especially in applications where corrosion is a problem:

• chemical processing;
• production of chlorates;
• desalination;
• marine applications.

Ti 6Al-4V class 5

Alloy Ti 6Al-4V, or grade 5 titanium, is the most commonly used. It accounts for 50% general consumption titanium all over the world.

Ease of use lies in its many benefits. Ti 6Al-4V can be heat treated to increase its strength. This alloy has high strength at low weight.

This is the best alloy to use in several industries such as aerospace, medical, marine and chemical processing industries. It can be used to create:

• aviation turbines;
• engine components;
• aircraft structural elements;
• aerospace fasteners;
• high-performance automatic parts;
• sports equipment.

Ti 6AL-4V ELI class 23

Grade 23 - surgical titanium. Ti 6AL-4V ELI, or Grade 23, is a higher purity version of Ti 6Al-4V. It can be made from rolls, strands, wires or flat wires. It is the best choice for any situation where a combination of high strength, low weight, good corrosion resistance and high toughness is required. It has excellent damage resistance.

It can be used in biomedical applications such as implantable components due to its biocompatibility, good fatigue strength. It can also be used in surgical procedures to fabricate these constructs:

• orthopedic pins and screws;
• clamps for ligature;
• surgical staples;
• springs;
• orthodontic appliances;
• cryogenic vessels;
• bone fixation devices.

Grade 12

Grade 12 titanium has excellent high quality weldability. It is a high strength alloy that provides good strength at high temperatures. Grade 12 titanium has characteristics similar to 300 series stainless steels.

Its ability to form different ways makes it useful in many applications. The high corrosion resistance of this alloy also makes it invaluable for manufacturing equipment. Class 12 can be used in the following industries:

• heat exchangers;
• hydrometallurgical applications;
• chemical production with elevated temperature;
• sea ​​and air components.

Ti5Al-2.5Sn

Ti 5Al-2.5Sn is an alloy that can provide good weldability with stability. It also has high temperature stability and high strength.

Ti 5Al-2.5Sn is mainly used in the aviation industry, as well as in cryogenic installations.

DEFINITION

Titanium- the twenty-second element of the Periodic table. Designation - Ti from the Latin "titanium". Located in the fourth period, IVB group. Refers to metals. The nuclear charge is 22.

Titanium is very common in nature; the titanium content in the earth's crust is 0.6% (wt.), i.e. higher than the content of such widely used metals in technology as copper, lead and zinc.

In the form of a simple substance, titanium is a silvery-white metal (Fig. 1). Refers to light metals. Refractory. Density - 4.50 g/cm 3 . The melting and boiling points are 1668 o C and 3330 o C, respectively. Corrosion-resistant when exposed to air at normal temperature, which is explained by the presence of a protective film of TiO 2 composition on its surface.

Rice. 1. Titanium. Appearance.

Atomic and molecular weight of titanium

Relative molecular weight of a substance(M r) is a number showing how many times the mass of a given molecule is greater than 1/12 of the mass of a carbon atom, and relative atomic mass of an element(A r) - how many times the average mass of atoms of a chemical element is greater than 1/12 of the mass of a carbon atom.

Since titanium exists in the free state in the form of monatomic Ti molecules, the values ​​of its atomic and molecular masses coincide. They are equal to 47.867.

Isotopes of titanium

It is known that titanium can occur in nature in the form of five stable isotopes 46Ti, 47Ti, 48Ti, 49Ti, and 50Ti. Their mass numbers are 46, 47, 48, 49 and 50, respectively. The atomic nucleus of the titanium isotope 46 Ti contains twenty-two protons and twenty-four neutrons, and the remaining isotopes differ from it only in the number of neutrons.

There are artificial titanium isotopes with mass numbers from 38 to 64, among which the most stable is 44 Ti with a half-life of 60 years, as well as two nuclear isotopes.

titanium ions

On the outer energy level of the titanium atom, there are four electrons that are valence:

1s 2 2s 2 2p 6 3s 2 3p 6 3d 2 4s 2 .

As a result of chemical interaction, titanium gives up its valence electrons, i.e. is their donor, and turns into a positively charged ion:

Ti 0 -2e → Ti 2+;

Ti 0 -3e → Ti 3+;

Ti 0 -4e → Ti 4+ .

Titanium molecule and atom

In the free state, titanium exists in the form of monatomic Ti molecules. Here are some properties that characterize the atom and molecule of titanium:

Titanium alloys

The main property of titanium, which contributes to its widespread use in modern technology, is the high heat resistance of both titanium itself and its alloys with aluminum and other metals. In addition, these alloys heat resistance - resistance to maintain high mechanical properties at elevated temperatures. All this makes titanium alloys very valuable materials for aircraft and rocket manufacturing.

At high temperatures, titanium combines with halogens, oxygen, sulfur, nitrogen and other elements. This is the basis for the use of titanium alloys with iron (ferrotittanium) as an additive to steel.

Examples of problem solving

EXAMPLE 1

EXAMPLE 2

The monument in honor of the conquerors of space was erected in Moscow in 1964. It took almost seven years (1958-1964) to design and build this obelisk. The authors had to solve not only architectural and artistic, but also technical problems. The first of them was the choice of materials, including facing. After long experiments, they settled on titanium sheets polished to a shine.

Indeed, in many characteristics, and above all in corrosion resistance, titanium surpasses the vast majority of metals and alloys. Sometimes (especially in popular literature) titanium is called the eternal metal. But first, let's talk about the history of this element.

Oxidized or not oxidized?

Until 1795, element No. 22 was called "menakin". So called it in 1791 by the English chemist and mineralogist William Gregor, who discovered a new element in the mineral menakanite (do not look for this name in modern mineralogical reference books - menakanite has also been renamed, now it is called ilmenite).

Four years after Gregor's discovery, the German chemist Martin Klaproth discovered a new chemical element in another mineral - rutile - and named it titanium in honor of the Elven queen Titania (Germanic mythology).

According to another version, the name of the element comes from the titans, the mighty sons of the goddess of the earth - Gaia (Greek mythology).

In 1797, it turned out that Gregor and Klaproth discovered the same element, and although Gregor had done this earlier, the name given to him by Klaproth was established for the new element.

But neither Gregor nor Klaproth succeeded in obtaining the elemental titanium. The white crystalline powder they isolated was titanium dioxide TiO 2 . For a long time none of the chemists succeeded in reducing this oxide, isolating pure metal from it.

In 1823, the English scientist W. Wollaston reported that the crystals he discovered in the metallurgical slags of the Merthyr Tydville plant were nothing but pure titanium. And 33 years later, the famous German chemist F. Wöhler proved that these crystals were again a titanium compound, this time a metal-like carbonitride.

For many years it was believed that metal Titanium was first obtained by Berzelius in 1825. in the reduction of potassium fluorotitanate with sodium metal. However, today, comparing the properties of titanium and the product obtained by Berzelius, it can be argued that the president of the Swedish Academy of Sciences was mistaken, because pure titabnum quickly dissolves in hydrofluoric acid (unlike many other acids), and Berzelius' metallic titanium successfully resisted its action.

In fact, Ti was first obtained only in 1875 by the Russian scientist D.K. Kirillov. The results of this work are published in his brochure Research on Titanium. But the work of a little-known Russian scientist went unnoticed. After another 12 years, a fairly pure product - about 95% titanium - was obtained by Berzelius's compatriots, the famous chemists L. Nilsson and O. Peterson, who reduced titanium tetrachloride with sodium metal in a steel hermetic bomb.

In 1895, the French chemist A. Moissan, reducing titanium dioxide with carbon in an arc furnace and subjecting the resulting material to double refining, obtained titanium containing only 2% impurities, mainly carbon. Finally, in 1910, the American chemist M. Hunter, having improved the method of Nilsson and Peterson, managed to obtain several grams of titanium with a purity of about 99%. That is why in most books the priority of obtaining metallic titanium is attributed to Hunter, and not to Kirillov, Nilson or Moissan.

However, neither Hunter nor his contemporaries predicted a great future for the titan. Only a few tenths of a percent of impurities were contained in the metal, but these impurities made titanium brittle, fragile, unsuitable for machining. Therefore, some titanium compounds found application earlier than the metal itself. Ti tetrachloride, for example, was widely used in the first world war to create smoke screens.

No. 22 in medicine

In 1908, in the USA and Norway, the production of white began not from lead and zinc compounds, as was done before, but from titanium dioxide. Such whitewash can paint a surface several times larger than the same amount of lead or zinc whitewash. In addition, titanium white has more reflectivity, they are not poisonous and do not darken under the influence of hydrogen sulfide. In the medical literature, a case is described when a person “took” 460 g of titanium dioxide at a time! (I wonder what he confused her with?) The "lover" of titanium dioxide did not experience any painful sensations. TiO 2 is part of some medicines, in particular ointments against skin diseases.

However, not medicine, but the paint and varnish industry consumes the largest amounts of TiO 2 . World production of this compound has far exceeded half a million tons per year. Enamels based on titanium dioxide are widely used as protective and decorative coatings for metal and wood in shipbuilding, construction and mechanical engineering. At the same time, the service life of structures and parts is significantly increased. Titanium white is used to dye fabrics, leather and other materials.

Ti in industry

Titanium dioxide is a constituent of porcelain masses, refractory glasses, ceramic materials with high dielectric constant. As a filler that increases strength and heat resistance, it is introduced into rubber compounds. However, all the advantages of titanium compounds seem insignificant against the background of the unique properties of pure metallic titanium.

elemental titanium

In 1925, the Dutch scientists van Arkel and de Boer obtained high purity titanium - 99.9% using the iodide method (more on that below). Unlike the titanium obtained by Hunter, it had plasticity: it could be forged in the cold, rolled into sheets, tape, wire, and even the thinnest foil. But even this is not the main thing. Studies of the physicochemical properties of metallic titanium led to almost fantastic results. It turned out, for example, that titanium, being almost twice as light as iron (the density of titanium is 4.5 g/cm3), surpasses many steels in strength. Comparison with aluminum also turned out in favor of titanium: titanium is only one and a half times heavier than aluminum, but six times stronger and, most importantly, it retains its strength at temperatures up to 500 ° C (and with the addition of alloying elements - up to 650 ° C ), while the strength of aluminum and magnesium alloys drops sharply already at 300°C.

Titanium also has significant hardness: it is 12 times harder than aluminum, 4 times harder than iron and copper. Another important characteristic of a metal is its yield strength. The higher it is, the better the details of this metal resist operational loads, the longer they retain their shape and size. The yield strength of titanium is almost 18 times higher than that of aluminum.

Unlike most metals, titanium has significant electrical resistance: if the electrical conductivity of silver is taken as 100, then the electrical conductivity of copper is 94, aluminum is 60, iron and platinum is 15, and titanium is only 3.8. It is hardly necessary to explain that this property, like the non-magnetic nature of titanium, is of interest for radio electronics and electrical engineering.

Remarkable resistance of titanium against corrosion. On a plate made of this metal for 10 years of being in sea water, there were no signs of corrosion. The main rotors of modern heavy helicopters are made of titanium alloys. Rudders, ailerons and some other critical parts of supersonic aircraft are also made of these alloys. On many chemical industries today you can find whole apparatuses and columns made of titanium.

How is titanium obtained?

Price - that's what else slows down the production and consumption of titanium. Actually, the high cost is not a congenital defect of titanium. There is a lot of it in the earth's crust - 0.63%. The still high price of titanium is a consequence of the difficulty of extracting it from ores. It is explained by the high affinity of titanium for many elements and the strength of chemical bonds in its natural compounds. Hence the complexity of the technology. This is how the magnesium-thermal method of titanium production looks like, developed in 1940 by the American scientist V. Kroll.

Titanium dioxide is converted with chlorine (in the presence of carbon) into titanium tetrachloride:

HO 2 + C + 2CI 2 → HCI 4 + CO 2.

The process takes place in shaft electric furnaces at 800-1250°C. Another option is chlorination in the melt of alkali metal salts NaCl and KCl. The next operation (which is equally important and laborious) is the purification of TiCl 4 different ways and substances. Titanium tetrachloride in normal conditions is a liquid with a boiling point of 136°C.

It is easier to break the bond of titanium with chlorine than with oxygen. This can be done with magnesium by the reaction

TiCl 4 + 2Mg → T + 2MgCl 2 .

This reaction takes place in steel reactors at 900°C. The result is a so-called titanium sponge impregnated with magnesium and magnesium chloride. They are evaporated in a sealed vacuum apparatus at 950°C, and the titanium sponge is then sintered or melted into a compact metal.

The sodium-thermal method for obtaining metallic titanium is, in principle, not much different from the magnesium-thermal method. These two methods are the most widely used in industry. To obtain purer titanium, the iodide method proposed by van Arkel and de Boer is still used. The metallothermic titanium sponge is converted to TiI 4 iodide, which is then sublimated in vacuo. On their way, titap iodide vapor encounters titanium wire heated to 1400°C. In this case, the iodide decomposes, and a layer of pure titanium grows on the wire. This method of titanium production is inefficient and expensive; therefore, it is used in industry to a very limited extent.

Despite the labor and energy intensity of titanium production, it has already become one of the most important non-ferrous metallurgy sub-sectors. World titanium production is developing at a very fast pace. This can be judged even by the fragmentary information that gets into print.

It is known that in 1948 only 2 tons of titanium were smelted in the world, and after 9 years - already 20 thousand tons. This means that in 1957 20 thousand tons of titanium accounted for all countries, and in 1980 only the USA consumed. 24.4 thousand tons of titanium ... Until recently, it seems, titanium was called a rare metal - now it is the most important structural material. This is explained by only one thing: a rare combination useful properties element number 22. And, of course, the needs of technology.

The role of titanium as a structural material, the basis of high-strength alloys for aviation, shipbuilding and rocketry, is rapidly increasing. It is in alloys that most of the titanium smelted in the world goes. A widely known alloy for the aviation industry, consisting of 90% titanium, 6% aluminum and 4% vanadium. In 1976, the American press reported on a new alloy for the same purpose: 85% titanium, 10% vanadium, 3% aluminum and 2% iron. It is claimed that this alloy is not only better, but also more economical.

In general, titanium alloys include a lot of elements, up to platinum and palladium. The latter (in the amount of 0.1-0.2%) increase the already high chemical resistance of titanium alloys.

The strength of titanium is also increased by such "alloying additives" as nitrogen and oxygen. But together with strength, they increase the hardness and, most importantly, the brittleness of titanium, so their content is strictly regulated: no more than 0.15% oxygen and 0.05% nitrogen are allowed in the alloy.

Despite the fact that titanium is expensive, replacing it with cheaper materials in many cases turns out to be economically viable. Here is a typical example. The case of a chemical apparatus made of stainless steel costs 150 rubles, and of a titanium alloy - 600 rubles. But at the same time, a steel reactor serves only 6 months, and a titanium one - 10 years. Add the cost of replacing steel reactors, the forced downtime of equipment - and it becomes obvious that using expensive titanium can be more profitable than steel.

Significant amounts of titanium are used in metallurgy. There are hundreds of grades of steels and other alloys that contain titanium as an alloying addition. It is introduced to improve the structure of metals, increase strength and corrosion resistance.

Some nuclear reactions must take place in an almost absolute void. With mercury pumps, the rarefaction can be brought up to several billionths of an atmosphere. But this is not enough, and mercury pumps are incapable of more. Further pumping of air is carried out by special titanium pumps. In addition, to achieve even greater rarefaction, fine titanium is sprayed onto the inner surface of the chamber where the reactions take place.

Titanium is often called the metal of the future. The facts that science and technology already have at their disposal convince us that this is not entirely true - titanium has already become the metal of the present.

Perovskite and sphene. Ilmenite - iron metatitanate FeTiO 3 - contains 52.65% TiO 2. The name of this mineral is due to the fact that it was found in the Urals in the Ilmensky mountains. The largest placers of ilmenite sands are found in India. Another important mineral, rutile, is titanium dioxide. Titanomagnetites are also of industrial importance - natural mixture ilmenite with iron minerals. There are rich deposits of titanium ores in the USSR, USA, India, Norway, Canada, Australia and other countries. Not so long ago, geologists discovered a new titanium-containing mineral in the Northern Baikal region, which was named landauite in honor of the Soviet physicist Academician L. D. Landau. In total, more than 150 significant ore and placer titanium deposits are known on the globe.

The most significant for the national economy were and remain alloys and metals, combining lightness and strength. Titanium belongs to this category of materials and, in addition, has excellent corrosion resistance.

Titanium is a transition metal of the 4th group of the 4th period. Its molecular weight is only 22, which indicates the lightness of the material. At the same time, the substance is distinguished by exceptional strength: among all structural materials, it is titanium that has the highest specific strength. Color is silvery white.

What is titanium, the video below will tell:

Concept and features

Titanium is quite common - it takes 10th place in terms of content in the earth's crust. However, it was only in 1875 that a truly pure metal was isolated. Prior to this, the substance was either obtained with impurities, or its compounds were called metallic titanium. This confusion led to the fact that the metal compounds were used much earlier than the metal itself.

This is due to the peculiarity of the material: the most insignificant impurities significantly affect the properties of a substance, sometimes completely depriving it of its inherent qualities.

Thus, the smallest fraction of other metals deprives titanium of heat resistance, which is one of its valuable qualities. And a small addition of a non-metal turns a durable material into a brittle and unsuitable for use.

This feature immediately divided the resulting metal into 2 groups: technical and pure.

• First are used in cases where strength, lightness and corrosion resistance are most needed, since titanium never loses the last quality.
• High purity material used where a material is needed that works under very high loads and high temperatures, but at the same time is lightweight. This, of course, is aircraft and rocket science.

The second special feature of matter is anisotropy. Some of its physical qualities change depending on the application of forces, which must be taken into account when applying.

Under normal conditions, the metal is inert, does not corrode either in sea water or in sea or city air. Moreover, it is the most biologically inert substance known, due to which titanium prostheses and implants are widely used in medicine.

At the same time, when the temperature rises, it begins to react with oxygen, nitrogen, and even hydrogen, and absorbs gases in liquid form. This unpleasant feature makes it extremely difficult both to obtain the metal itself and to manufacture alloys based on it.

The latter is possible only when using vacuum equipment. The most complex production process has turned a fairly common element into a very expensive one.

Bonding with other metals

Titanium occupies an intermediate position between the other two well-known structural materials - aluminum and iron, or rather, iron alloys. In many respects, the metal is superior to its "competitors":

• the mechanical strength of titanium is 2 times higher than that of iron, and 6 times higher than that of aluminum. In this case, the strength increases with decreasing temperature;
• corrosion resistance is much higher than that of iron and even aluminum;
• At normal temperatures, titanium is inert. However, when it rises to 250 C, it begins to absorb hydrogen, which affects the properties. In terms of chemical activity, it is inferior to magnesium, but, alas, it surpasses iron and aluminum;
• the metal conducts electricity much weaker: its electrical resistivity is 5 times higher than that of iron, 20 times higher than that of aluminum, and 10 times higher than that of magnesium;
• thermal conductivity is also much lower: 3 times less than iron 1, and 12 times less than aluminum. However, this property results in a very low coefficient of thermal expansion.

Advantages and disadvantages

In fact, titanium has many disadvantages. But the combination of strength and lightness is so in demand that neither the complex manufacturing method nor the need for exceptional purity stop metal consumers.

The undoubted advantages of the substance include:

• low density, which means very little weight;
• exceptional mechanical strength of both the titanium metal itself and its alloys. With increasing temperature, titanium alloys outperform all aluminum and magnesium alloys;
• the ratio of strength and density - specific strength, reaches 30–35, which is almost 2 times higher than that of the best structural steels;
• in air, titanium is coated with a thin layer of oxide, which provides excellent corrosion resistance.

Metal also has its drawbacks:

• Corrosion resistance and inertness only applies to non-active surface products. Titanium dust or shavings, for example, spontaneously ignite and burn at a temperature of 400 C;
• a very complex method of obtaining titanium metal provides a very high cost. The material is much more expensive than iron, or;
• the ability to absorb atmospheric gases with increasing temperature requires the use of vacuum equipment for melting and obtaining alloys, which also significantly increases the cost;
• titanium has poor antifriction properties - it does not work for friction;
• metal and its alloys are prone to hydrogen corrosion, which is difficult to prevent;
• titanium is difficult to machine. Welding it is also difficult due to the phase transition during heating.

Titanium sheet (photo)

Properties and characteristics

Strongly dependent on cleanliness. Reference data describe, of course, pure metal, but the characteristics of technical titanium can vary markedly.

• The density of the metal decreases when heated from 4.41 to 4.25 g/cm3. The phase transition changes the density by only 0.15%.
• The melting point of the metal is 1668 C. The boiling point is 3227 C. Titanium is a refractory substance.
• On average, the tensile strength is 300–450 MPa, however, this figure can be increased to 2000 MPa by resorting to hardening and aging, as well as the introduction of additional elements.
• On the HB scale, the hardness is 103 and this is not the limit.
• The heat capacity of titanium is low - 0.523 kJ/(kg K).
• Specific electrical resistance - 42.1 10 -6 ohm cm.
• Titanium is a paramagnet. As the temperature decreases, its magnetic susceptibility decreases.
• Metal as a whole is characterized by ductility and malleability. However, these properties are strongly influenced by oxygen and nitrogen in the alloy. Both elements make the material brittle.

The substance is resistant to many acids, including nitric, sulfuric in low concentrations and almost all organic acids except formic. This quality ensures that titanium is in demand in the chemical, petrochemical, paper industries, and so on.

Structure and composition

Titanium - although it is a transition metal, and its electrical resistivity is low, nevertheless, it is a metal and conducts electric current, which means an ordered structure. When heated to a certain temperature, the structure changes:

• up to 883 C, the α-phase is stable with a density of 4.55 g / cu. see It is distinguished by a dense hexagonal lattice. Oxygen dissolves in this phase with the formation of interstitial solutions and stabilizes the α-modification - pushes the temperature limit;
• above 883 C, the β-phase with a body-centered cubic lattice is stable. Its density is somewhat less - 4.22 g / cu. see. Hydrogen stabilizes this structure - when it is dissolved in titanium, interstitial solutions and hydrides are also formed.

This feature makes the work of the metallurgist very difficult. The solubility of hydrogen decreases sharply when titanium is cooled, and hydrogen hydride, the γ-phase, precipitates in the alloy.

It causes cold cracks during welding, so manufacturers have to work extra hard after melting the metal to clean it of hydrogen.

About where you can find and how to make titanium, we will tell below.

This video is dedicated to the description of titanium as a metal:

Production and mining

Titanium is very common, so with ores containing metal, and in quite large quantities, there are no problems. The raw materials are rutile, anatase and brookite - titanium dioxide in various modifications, ilmenite, pyrophanite - compounds with iron, and so on.

But it is complex and requires expensive equipment. The methods of obtaining are somewhat different, since the composition of the ore is different. For example, the scheme for obtaining metal from ilmenite ores looks like this:

• obtaining titanium slag - the rock is loaded into an electric arc furnace together with a reducing agent - anthracite, charcoal and heated to 1650 C. At the same time, iron is separated, which is used to obtain cast iron and titanium dioxide in the slag;
• slag is chlorinated in mine or salt chlorinators. The essence of the process is to convert solid dioxide into gaseous titanium tetrachloride;
• in resistance furnaces in special flasks, the metal is reduced with sodium or magnesium from chloride. As a result, a simple mass is obtained - a titanium sponge. This is technical titanium quite suitable for the manufacture of chemical equipment, for example;
• if a purer metal is required, they resort to refining - in this case, the metal reacts with iodine in order to obtain gaseous iodide, and the latter, under the influence of temperature - 1300-1400 C, and electric current, decomposes, releasing pure titanium. Electricity is fed through a titanium wire stretched in a retort, onto which a pure substance is deposited.

To obtain titanium ingots, the titanium sponge is melted down in a vacuum furnace to prevent hydrogen and nitrogen from dissolving.

The price of titanium per 1 kg is very high: depending on the degree of purity, the metal costs from $25 to $40 per 1 kg. On the other hand, the case of an acid-resistant stainless steel apparatus will cost 150 rubles. and will last no more than 6 months. Titanium will cost about 600 r, but is operated for 10 years. There are many titanium production facilities in Russia.

Areas of use

The influence of the degree of purification on the physical and mechanical properties forces us to consider it from this point of view. So, technical, that is, not the purest metal, has excellent corrosion resistance, lightness and strength, which determines its use:

• chemical industry– heat exchangers, pipes, casings, pump parts, fittings and so on. The material is indispensable in areas where acid resistance and strength are required;
• transport industry- the substance is used to make vehicles from trains to bicycles. In the first case, the metal provides a smaller mass of compounds, which makes traction more efficient, in the latter it gives lightness and strength, it is not for nothing that a titanium bicycle frame is considered the best;
• naval affairs- titanium is used to make heat exchangers, exhaust silencers for submarines, valve, propellers and so on;
• in construction widely used - titanium - an excellent material for finishing facades and roofs. Along with strength, the alloy provides another advantage important for architecture - the ability to give products the most bizarre configuration, the ability to shape the alloy is unlimited.

The pure metal is also very resistant to high temperatures and retains its strength. The application is obvious:

• rocket and aircraft industry - sheathing is made from it. Engine parts, fasteners, chassis parts and so on;
• medicine - biological inertness and lightness makes titanium a much more promising material for prosthetics, up to heart valves;
• cryogenic technology - titanium is one of the few substances that, when the temperature drops, only become stronger and does not lose plasticity.

Titanium is a structural material of the highest strength with such lightness and ductility. These unique qualities provide him with an increasingly important role in the national economy.

The video below will tell you where to get titanium for a knife:

Everything you need to know about titanium as well as chromium and tungsten

Many are interested in the question: what is the hardest metal in the world? This is a titan. This solid substance will be the subject of most of the article. We will also get a little acquainted with such hard metals as chromium and tungsten.

9 interesting facts about titanium

1. There are several versions of why the metal got its name. According to one theory, he was named after the Titans, fearless supernatural beings. According to another version, the name comes from Titania, the queen of the fairies.
2. Titanium was discovered at the end of the 18th century by a German and English chemist.
3. Titanium has not been used in industry for a long time due to its natural brittleness.
4. At the beginning of 1925, after a series of experiments, chemists obtained pure titanium.
5. Titanium shavings are flammable.
6. It is one of the lightest metals.
7. Titanium can only melt at temperatures above 3200 degrees.
8. Boils at a temperature of 3300 degrees.
9. Titanium has a silver color.

The history of the discovery of titanium

The metal, which was later called titanium, was discovered by two scientists - the Englishman William Gregor and the German Martin Gregor Klaproth. Scientists worked in parallel, and did not intersect with each other. The difference between the discoveries is 6 years.

William Gregor named his discovery menakin.

More than 30 years later, the first titanium alloy was obtained, which turned out to be extremely brittle and could not be used anywhere. It is believed that only in 1925 titanium was isolated in its pure form, which became one of the most demanded metals in industry.

It is proved that the Russian scientist Kirillov in 1875 managed to extract pure titanium. He published a pamphlet detailing his work. However, the research of a little-known Russian went unnoticed.

General information about titanium

Titanium alloys are a lifesaver for mechanics and engineers. For example, the body of an aircraft is made of titanium. During the flight, it reaches speeds several times greater than the speed of sound. The titanium case heats up to temperatures above 300 degrees, and does not melt.

Metal closes the top ten "Most common metals in nature." Large deposits have been discovered in South Africa, China, and a lot of titanium in Japan, India, and Ukraine.

The total amount of the world's titanium reserves is more than 700 million tons. If the rate of production remains the same, titanium will last another 150-160 years.

The largest producer of the hardest metal in the world - Russian enterprise"VSMPO-Avisma", which satisfies a third of the world's needs.

Titanium properties

1. Corrosion resistance.
2. High mechanical strength.
3. Low density.

The atomic weight of titanium is 47.88 amu, the serial number in the chemical periodic table is 22. Outwardly, it is very similar to steel.

The mechanical density of the metal is 6 times higher than that of aluminum, 2 times higher than that of iron. It can combine with oxygen, hydrogen, nitrogen. When paired with carbon, the metal forms incredibly hard carbides.

The thermal conductivity of titanium is 4 times less than that of iron, and 13 times less than that of aluminum.

Titanium mining process

In the land of titan a large number of However, extracting it from the bowels costs a lot of money. For development, the iodide method is used, the author of which is Van Arkel de Boer.

The method is based on the ability of the metal to combine with iodine; after the decomposition of this compound, pure titanium, free from impurities, can be obtained.

The most interesting things from titanium:

• prostheses in medicine;
• mobile device boards;
• rocket systems for space exploration;
• pipelines, pumps;
• canopies, cornices, exterior cladding of buildings;
• most parts (chassis, skin).

Applications of titanium

Titanium is actively used in the military, medicine, and jewelry. He was given the unofficial name "metal of the future". Many say that it helps to turn a dream into reality.

The hardest metal in the world was originally used in the military and defense sphere. Today, the main consumer of titanium products is the aircraft industry.

Titanium is a versatile structural material. For many years it has been used to create aircraft turbines. In aircraft engines, titanium is used to make fan elements, compressors, and disks.

The design of modern aircraft can contain up to 20 tons of titanium alloy.

The main areas of application of titanium in the aircraft industry:

• products of a spatial form (edging of doors, hatches, sheathing, flooring);
• units and components that are subject to heavy loads (wing brackets, landing gear, hydraulic cylinders);
• engine parts (body, blades for compressors).

Titanium in space, rocket and shipbuilding

Thanks to titanium, man was able to pass through sound barrier, and burst into space. It was used to create manned missile systems. Titanium can withstand cosmic radiation, temperature changes, speed of movement.

This metal has a low density, which is important in the shipbuilding industry. Products made of titanium are light, which means that weight is reduced, its maneuverability, speed, and range are increased. If the ship's hull is sheathed with titanium, it will not need to be painted for many years - titanium does not rust in sea water (corrosion resistance).

Most often, this metal is used in shipbuilding for the manufacture of turbine engines, steam boilers, and condenser tubes.

Oil industry and titanium

Ultra-deep drilling is considered to be a promising area for the use of titanium alloys. To study and extract underground riches, there is a need to penetrate deep underground - over 15 thousand meters. Drill pipes made of aluminum, for example, will break due to their own gravity, and only titanium alloys can reach really great depths.

Not so long ago, titanium began to be actively used to create wells on the sea shelves. Specialists use titanium alloys as equipment:

• oil production installations;
• pressure vessels;
• deep water pumps, pipelines.

Titanium in sports, medicine

Titanium is extremely popular in the sports field because of its strength and lightness. A few decades ago, a bicycle was made from titanium alloys, the first sports equipment from the very solid material in the world. A modern bicycle consists of a titanium body, the same brake and seat springs.

Japan has created titanium golf clubs. These devices are light and durable, but extremely expensive in price.

Titanium is used to make most of the items that are in the backpack of climbers and travelers - tableware, cooking kits, racks for strengthening tents. Titanium ice axes are a very popular sports equipment.

This metal is in high demand in the medical industry. Most surgical instruments are made of titanium - lightweight and comfortable.

Another area of ​​application of the metal of the future is the creation of prostheses. Titanium perfectly "combines" with the human body. Doctors called this process "true relationship." Titanium structures are safe for muscles and bones, rarely cause an allergic reaction, and do not break down under the influence of liquid in the body. Prostheses made of titanium are resistant and withstand enormous physical loads.

Titanium is an amazing metal. It helps a person to achieve unprecedented heights in various areas of life. It is loved and revered for its strength, lightness and long years of service.

Chromium is one of the hardest metals.

Interesting Chromium Facts

1. The name of the metal comes from the Greek word "chroma", which means paint.
2. In natural environment chromium does not occur in its pure form, but only in the form of chromium iron ore, a double oxide.
3. The largest metal deposits are located in South Africa, Russia, Kazakhstan and Zimbabwe.
4. Density of metal - 7200kg/m3.
5. Chromium melts at 1907 degrees.
6. Boils at a temperature of 2671 degrees.
7. Completely pure without impurities, chromium is characterized by malleability and toughness. In combination with oxygen, nitrogen or hydrogen, the metal becomes brittle and very hard.
8. This silver-white metal was discovered by the Frenchman Louis Nicolas Vauquelin at the end of the 18th century.

Chromium metal properties

Chrome has a very high hardness, it can cut glass. It is not oxidized by air, moisture. If the metal is heated, oxidation will occur only on the surface.

More than 15,000 tons of pure chromium are consumed per year. The leader in the production of the purest chromium is considered English company Bell Metals.

Most chromium is consumed in the USA, Western countries Europe and Japan. The chromium market is volatile and prices span a wide range.

Areas of use of chromium

It is most often used to create alloys and electroplated coatings (chromium plating for transport).

Chromium is added to steel, which improves the physical properties of the metal. These alloys are most in demand in ferrous metallurgy.

The most popular steel grade consists of chromium (18%) and nickel (8%). Such alloys perfectly resist oxidation, corrosion, and are strong even at high temperatures.

Heating furnaces are made from steel, which contains a third of chromium.

What else is made of chrome?

1. Barrels of firearms.
2. Hull of submarines.
3. Bricks, which are used in metallurgy.

Another extremely hard metal is tungsten.

Interesting facts about tungsten

1. The name of the metal in German (“Wolf Rahm”) means “wolf foam”.
2. It is the most refractory metal in the world.
3. Tungsten has a light gray tint.
4. The metal was discovered at the end of the 18th century (1781) by the Swede Karl Scheele.
5. Tungsten melts at 3422 degrees, boils at 5900.
6. The metal has a density of 19.3 g/cm³.
7. Atomic mass - 183.85, an element of group VI in the periodic system of Mendeleev (serial number - 74).

Tungsten mining process

Tungsten belongs to a large group of rare metals. It also includes rubidium, molybdenum. This group is characterized by a low prevalence of metals in nature and a small scale of consumption.

Getting tungsten consists of 3 stages:

• separation of metal from ore, its accumulation in solution;
• isolation of the compound, its purification;
• extraction of pure metal from the finished chemical compound.
• The starting material for obtaining tungsten is scheelite and wolframite.

Applications of tungsten

Tungsten is the basis of most durable alloys. Aircraft engines, parts of electrovacuum devices, incandescent filaments are made from it.
The high density of the metal makes it possible to use tungsten to create ballistic missiles, bullets, counterweights, artillery shells.

Tungsten-based compounds are used for the processing of other metals, in the mining industry (well drilling), paintwork, and textiles (as a catalyst for organic synthesis).

From complex tungsten compounds make:

• wires - used in heating furnaces;
• tapes, foil, plates, sheets - for rolling and flat forging.

Titanium, chromium and tungsten top the list of "The Hardest Metals in the World". They are used in many areas of human activity - aircraft and rocket science, the military field, construction, and at the same time, this is far from a complete range of metal applications.