Titanium melts. The hardest metal in the world (Titanium, Chromium and Tungsten). Areas of use of chromium

The most significant for National economy there were and still are alloys and metals that combine 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.

• The 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.

Pros and cons

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 that with ores containing metal, and in fairly large quantities, there are no difficulties. 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 produce 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 - while 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, valves, 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:

Section 1. History and occurrence of titanium in nature.

Titanium — this is an element of a side subgroup of the fourth group, the fourth period of the periodic system of chemical elements of D. I. Dmitry Ivanovich Mendeleev, with atomic number 22. A simple substance titanium(CAS number: 7440-32-6) - light silvery white. It exists in two crystalline modifications: α-Ti with a hexagonal close-packed lattice, β-Ti with a cubic body-centered packing, the temperature of the polymorphic transformation α↔β is 883 °C. Melting point 1660±20 °C.

History and presence in nature of titanium

Titanium was named after the ancient Greek characters Titans. The German chemist Martin Klaproth named it this way for his personal reasons, unlike the French who tried to give names in accordance with the chemical characteristics of the element, but since then the properties of the element were unknown, such a name was chosen.

Titanium is the 10th element in terms of number of it on our planet. The amount of titanium in the earth's crust is 0.57% by weight and 0.001 milligrams per 1 liter of sea water. Titanium deposits are located on the territory of: the Republic of South Africa, Ukraine, Russian Federation, Kazakhstan, Japan, Australia, India, Ceylon, Brazil and South Korea.

According to the physical properties, titanium is light silvery metal, in addition, a high viscosity is characteristic at machining and is prone to sticking to the cutting tool, so special lubricants or sprays are used to eliminate this effect. At room temperature, it is covered with a translucent film of TiO2 oxide, due to which it is resistant to corrosion in most aggressive environments, except for alkalis. Titanium dust has the ability to explode, with a flash point of 400 °C. Titanium shavings are flammable.

To produce pure titanium or its alloys, in most cases, titanium dioxide is used with a small number of compounds included in it. For example, a rutile concentrate obtained by beneficiation of titanium ores. But the reserves of rutile are extremely small, and in connection with this, the so-called synthetic rutile or titanium slag, obtained during the processing of ilmenite concentrates, is used.

The discoverer of titanium is considered to be 28-year-old English monk William Gregor. In 1790, while conducting mineralogical surveys in his parish, he drew attention to the prevalence and unusual properties of black sand in the valley of Menaken in the south-west of Britain and began to explore it. AT sand the priest discovered grains of a black shiny mineral, attracted by an ordinary magnet. Obtained in 1925 by Van Arkel and de Boer by the iodide method, the purest titanium turned out to be ductile and technological metal with many valuable properties that attracted the attention of a wide range of designers and engineers. In 1940, Croll proposed a magnesium-thermal method for extracting titanium from ores, which is still the main one at the present time. In 1947, the first 45 kg of commercially pure titanium were produced.

In the Periodic Table of the Elements Mendeleev Dmitry Ivanovich titanium has serial number 22. The atomic mass of natural titanium, calculated from the results of studies of its isotopes, is 47.926. So, the nucleus of a neutral titanium atom contains 22 protons. The number of neutrons, that is, neutral uncharged particles, is different: more often 26, but can vary from 24 to 28. Therefore, the number of titanium isotopes is different. In total, 13 isotopes of element No. 22 are now known. Natural titanium consists of a mixture of five stable isotopes, titanium-48 is the most widely represented, its share in natural ores is 73.99%. Titanium and other elements of the IVB subgroup are very similar in properties to the elements of the IIIB subgroup (scandium group), although they differ from the latter in their ability to exhibit a large valence. The similarity of titanium with scandium, yttrium, as well as with elements of the VB subgroup - vanadium and niobium, is also expressed in the fact that titanium is often found in natural minerals together with these elements. With monovalent halogens (fluorine, bromine, chlorine and iodine), it can form di-tri- and tetra compounds, with sulfur and elements of its group (selenium, tellurium) - mono- and disulfides, with oxygen - oxides, dioxides and trioxides.

Titanium also forms compounds with hydrogen (hydrides), nitrogen (nitrides), carbon (carbides), phosphorus (phosphides), arsenic (arsides), as well as compounds with many metals - intermetallic compounds. Titanium forms not only simple, but also numerous complex compounds; many of its compounds with organic substances are known. As can be seen from the list of compounds in which titanium can participate, it is chemically very active. And at the same time, titanium is one of the few metals with exceptionally high corrosion resistance: it is practically eternal in the air, in cold and boiling water, it is very resistant in sea water, in solutions of many salts, inorganic and organic acids. In terms of its corrosion resistance in sea water, it surpasses all metals, with the exception of noble ones - gold, platinum, etc., most types of stainless steel, nickel, copper and other alloys. In water, in many aggressive environments, pure titanium is not subject to corrosion. Resists titanium and erosion corrosion, which occurs as a result of a combination of chemical and mechanical effects on. In this regard, it is not inferior to the best grades of stainless steels, cuprum-based alloys and other structural materials. Titanium also resists fatigue corrosion well, which often manifests itself in the form of violations of the integrity and strength of the metal (cracking, local corrosion centers, etc.). The behavior of titanium in many aggressive environments, such as nitrogen, hydrochloric, sulfuric, "aqua regia" and other acids and alkalis, is surprising and admirable for this metal.

Titanium is a very refractory metal. For a long time it was believed that it melts at 1800 ° C, but in the mid-50s. English scientists Diardorf and Hayes established the melting point for pure elemental titanium. It amounted to 1668 ± 3 ° C. In terms of its refractoriness, titanium is second only to such metals as tungsten, tantalum, niobium, rhenium, molybdenum, platinoids, zirconium, and among the main structural metals it is in first place. The most important feature of titanium as a metal is its unique physical and chemical properties: low density, high strength, hardness, etc. The main thing is that these properties do not change significantly at high temperatures.

Titanium is a light metal, its density at 0°C is only 4.517 g/cm8, and at 100°C it is 4.506 g/cm3. Titanium belongs to the group of metals with a specific gravity of less than 5 g/cm3. This includes all alkali metals (sodium, cadium, lithium, rubidium, cesium) with a specific gravity of 0.9-1.5 g / cm3, magnesium (1.7 g / cm3), (2.7 g / cm3), etc. .Titanium is more than 1.5 times heavier aluminum, and in this, of course, he loses to him, but on the other hand, it is 1.5 times lighter than iron (7.8 g / cm3). However, occupying an intermediate position in terms of specific density between aluminum and iron, titanium surpasses them many times over in its mechanical properties.). Titanium has a significant hardness: it is 12 times harder than aluminum, 4 times gland and cuprum. Another important characteristic of a metal is its yield strength. The higher it is, the better the parts made of this metal resist operational loads. The yield strength of titanium is almost 18 times higher than that of aluminum. The specific strength of titanium alloys can be increased by 1.5-2 times. Its high mechanical properties are well preserved at temperatures up to several hundred degrees. Pure titanium is suitable for all types of work in hot and cold conditions: it can be forged as iron, pull and even make a wire out of it, roll it into sheets, tapes, into foil up to 0.01 mm thick.

Unlike most metals, titanium has significant electrical resistance: if the electrical conductivity of silver is taken as 100, then the electrical conductivity cuprum equal to 94, aluminum - 60, iron and platinum-15, while titanium is only 3.8. Titanium is a paramagnetic metal, it is not magnetized, like in a magnetic field, but it is not pushed out of it, like. Its magnetic susceptibility is very weak, this property can be used in construction. Titanium has a relatively low thermal conductivity, only 22.07 W / (mK), which is approximately 3 times lower than the thermal conductivity of iron, 7 times of magnesium, 17-20 times of aluminum and cuprum. Accordingly, the coefficient of linear thermal expansion of titanium is lower than that of other structural materials: at 20 C, it is 1.5 times lower than that of iron, 2 - for cuprum, and almost 3 - for aluminum. Thus, titanium is a poor conductor of electricity and heat.

Today, titanium alloys are widely used in aviation technology. Titanium alloys were first used on an industrial scale in the construction of aircraft jet engines. The use of titanium in the design of jet engines makes it possible to reduce their weight by 10...25%. In particular, compressor discs and blades, air intake parts, guide vanes and fasteners are made from titanium alloys. Titanium alloys are indispensable for supersonic aircraft. The growth of flight speeds aircraft led to an increase in the temperature of the skin, as a result of which aluminum alloys ceased to meet the requirements imposed by aviation technology at supersonic speeds. The skin temperature in this case reaches 246...316 °C. Under these conditions, titanium alloys turned out to be the most acceptable material. In the 70s, the use of titanium alloys for the airframe of civil aircraft increased significantly. In the medium-haul aircraft TU-204, the total mass of parts made of titanium alloys is 2570 kg. The use of titanium in helicopters is gradually expanding, mainly for parts of the main rotor system, drive, and control system. An important place is occupied by titanium alloys in rocket science.

Due to the high corrosion resistance in sea water, titanium and its alloys are used in shipbuilding for the manufacture of propellers, ship plating, submarines, torpedoes, etc. Shells do not stick to titanium and its alloys, which sharply increase the resistance of the vessel when it moves. Gradually, the areas of application of titanium are expanding. Titanium and its alloys are used in the chemical, petrochemical, pulp and paper and Food Industry, non-ferrous metallurgy, power engineering, electronics, nuclear technology, electroplating, in the manufacture of weapons, for the manufacture of armor plates, surgical instruments, surgical implants, desalination plants, parts of racing cars, sports equipment (golf clubs, climbing equipment), parts of watches and even jewelry. Nitriding of titanium leads to the formation of a golden film on its surface, which is not inferior in beauty to real gold.

The discovery of TiO2 was made almost simultaneously and independently by the Englishman W. Gregor and the German chemist M. G. Klaproth. W. Gregor, investigating the composition of the magnetic glandular sand(Creed, Cornwall, England, 1791), isolated a new "earth" (oxide) of an unknown metal, which he called menaken. In 1795, the German chemist Klaproth discovered in mineral rutile a new element and called it titanium. Two years later, Klaproth established that rutile and menakenic oxides are oxides of the same element, behind which the name “titanium” proposed by Klaproth remained. After 10 years, the discovery of titanium took place for the third time. The French scientist L. Vauquelin discovered titanium in anatase and proved that rutile and anatase are identical titanium oxides.

The discovery of TiO2 was made almost simultaneously and independently by the Englishman W. Gregor and the German chemist M. G. Klaproth. W. Gregor, studying the composition of magnetic ferruginous sand (Creed, Cornwall, England, 1791), isolated a new "earth" (oxide) of an unknown metal, which he called menaken. In 1795, the German chemist Klaproth discovered in mineral rutile a new element and called it titanium. Two years later, Klaproth established that rutile and menaken earth are oxides of the same element, behind which the name "titanium" proposed by Klaproth remained. After 10 years, the discovery of titanium took place for the third time. The French scientist L. Vauquelin discovered titanium in anatase and proved that rutile and anatase are identical titanium oxides.

The first sample of metallic titanium was obtained in 1825 by J. Ya. Berzelius. Due to the high chemical activity of titanium and the complexity of its purification, the Dutch A. van Arkel and I. de Boer obtained a pure Ti sample in 1925 by thermal decomposition of titanium iodide TiI4 vapor.

Titanium is the 10th most abundant in nature. The content in the earth's crust is 0.57% by mass, in sea water 0.001 mg / l. In ultrabasic rocks 300 g/t, in basic rocks 9 kg/t, in acidic rocks 2.3 kg/t, in clays and shales 4.5 kg/t. In the earth's crust, titanium is almost always tetravalent and is present only in oxygen compounds. It does not occur in free form. Titanium under conditions of weathering and precipitation has a geochemical affinity for Al2O3. It is concentrated in bauxites of the weathering crust and in marine clayey sediments. The transfer of titanium is carried out in the form of mechanical fragments of minerals and in the form of colloids. Up to 30% TiO2 by weight accumulates in some clays. Titanium minerals are resistant to weathering and form large concentrations in placers. More than 100 minerals containing titanium are known. The most important of them are: rutile TiO2, ilmenite FeTiO3, titanomagnetite FeTiO3 + Fe3O4, perovskite CaTiO3, titanite CaTiSiO5. There are primary titanium ores - ilmenite-titanomagnetite and placer - rutile-ilmenite-zircon.

Main ores: ilmenite (FeTiO3), rutile (TiO2), titanite (CaTiSiO5).

In 2002, 90% of the mined titanium was used for the production of titanium dioxide TiO2. World production of titanium dioxide was 4.5 million tons per year. Proven reserves of titanium dioxide (without Russian Federation) are about 800 million tons. For 2006, according to the US Geological Survey, in terms of titanium dioxide and excluding Russian Federation, the reserves of ilmenite ores are 603-673 million tons, and rutile - 49.7-52.7 million tons. Thus, at the current rate of production of the world's proven reserves of titanium (excluding the Russian Federation), it will last more than 150 years.

Russia has the world's second largest reserves of titanium after China. The mineral resource base of titanium in the Russian Federation consists of 20 deposits (of which 11 are primary and 9 placer), fairly evenly dispersed throughout the country. The largest of the explored deposits (Yaregskoye) is located 25 km from the city of Ukhta (Komi Republic). The reserves of the deposit are estimated at 2 billion tons of ore with an average titanium dioxide content of about 10%.

The world's largest producer of titanium Russian organization"VSMPO-AVISMA".

As a rule, the starting material for the production of titanium and its compounds is titanium dioxide with a relatively small amount of impurities. In particular, it can be a rutile concentrate obtained during the beneficiation of titanium ores. However, the reserves of rutile in the world are very limited, and the so-called synthetic rutile or titanium slag, obtained during the processing of ilmenite concentrates, is more often used. To obtain titanium slag, ilmenite concentrate is reduced in an electric arc furnace, while iron is separated into a metal phase (), and not reduced titanium oxides and impurities form a slag phase. Rich slag is processed by the chloride or sulfuric acid method.

In pure form and in the form of alloys

Titanium monument to Gagarin on Leninsky Prospekt in Moscow

metal is applied in: chemical industry(reactors, pipelines, pumps, pipeline accessories), military industry(body armor, armor and fire barriers in aviation, submarine hulls), industrial processes (desalination plants, processes pulp and paper), automotive industry, agricultural industry, food industry, piercing jewelry, medical industry (prostheses, osteoprostheses), dental and endodontic instruments, dental implants, sporting goods, jewelry trade items (Alexander Khomov), mobile phones, light alloys, etc. It is the most important structural material in aircraft, rocket, and shipbuilding.

Titanium casting is carried out in vacuum furnaces in graphite molds. Vacuum investment casting is also used. Due to technological difficulties, it is used in artistic casting to a limited extent. The first monumental cast titanium sculpture in the world is the monument to Yuri Gagarin on the square named after him in Moscow.

Titanium is an alloying addition in many alloyed steels and most special alloys.

Nitinol (nickel-titanium) is a shape memory alloy used in medicine and technology.

Titanium aluminides are very resistant to oxidation and heat-resistant, which in turn determined their use in aviation and automotive industry as structural materials.

Titanium is one of the most common getter materials used in high vacuum pumps.

White titanium dioxide (TiO2) is used in paints (such as titanium white) as well as in the manufacture of paper and plastics. Food additive E171.

Organotitanium compounds (eg tetrabutoxytitanium) are used as a catalyst and hardener in the chemical and paint industries.

Inorganic titanium compounds are used in the chemical, electronic, glass fiber industries as additives or coatings.

Titanium carbide, titanium diboride, titanium carbonitride are important components of superhard materials for metal processing.

Titanium nitride is used to coat tools, church domes and in the manufacture of costume jewelry, because. has a color similar to .

Barium titanate BaTiO3, lead titanate PbTiO3, and a number of other titanates are ferroelectrics.

There are many titanium alloys with different metals. Alloying elements are divided into three groups, depending on their effect on the temperature of polymorphic transformation: beta stabilizers, alpha stabilizers and neutral hardeners. The former lower the transformation temperature, the latter increase it, and the latter do not affect it, but lead to solution hardening of the matrix. Examples of alpha stabilizers: , oxygen, carbon, nitrogen. Beta stabilizers: molybdenum, vanadium, iron, chromium, Ni. Neutral hardeners: zirconium, silicon. Beta stabilizers, in turn, are divided into beta-isomorphic and beta-eutectoid-forming. The most common titanium alloy is the Ti-6Al-4V alloy (VT6 in the Russian classification).

In 2005 firm titanium corporation has published the following estimate of titanium consumption in the world:

13% - paper;

7% - mechanical engineering.

$15-25 per kilo, depending on purity.

The purity and grade of rough titanium (titanium sponge) is usually determined by its hardness, which depends on the content of impurities. The most common brands are TG100 and TG110.

The consumer goods market segment is currently the fastest growing segment of the titanium market. While 10 years ago this segment was only 1-2 of the titanium market, today it has grown to 8-10 of the market. Overall, titanium consumption in the consumer goods industry grew at about twice the rate of the entire titanium market. The use of titanium in sports is the most durable and takes the largest share in the application of titanium in consumer goods. The reason for the popularity of titanium in sports equipment is simple - it allows you to get a ratio of weight and strength superior to any other metal. The use of titanium in bicycles began about 25-30 years ago and was the first use of titanium in sports equipment. Ti3Al-2.5V ASTM Grade 9 alloy tubes are mainly used. Other parts made from titanium alloys include brakes, sprockets and seat springs. The use of titanium in the manufacture of golf clubs first began in the late 80s and early 90s by club manufacturers in Japan. Prior to 1994-1995, this application of titanium was virtually unknown in the US and Europe. That changed when Callaway introduced its Ruger titanium stick, called the Great Big Bertha, to the market. Due to the obvious benefits and well-thought-out marketing from Callaway, titanium sticks became an instant hit. Within a short period of time, titanium clubs have gone from the exclusive and expensive inventory of a small group of speculators to being widely used by most golfers while still being more expensive than steel clubs. I would like to cite the main, in my opinion, trends in the development of the golf market; it has gone from high-tech to mass production in a short 4-5 years, following the path of other industries with high labor costs such as the production of clothing, toys and consumer electronics, the production of golf clubs has gone into countries with the cheapest labor first to Taiwan, then to China, and now factories are being built in countries with even cheaper labor, such as Vietnam and Thailand, titanium is definitely used for drivers, where its superior qualities give a clear advantage and justify a higher price. However, titanium has not yet found very widespread use on subsequent clubs, as the significant increase in costs is not matched by a corresponding improvement in the game. Currently, drivers are mainly produced with a forged striking surface, a forged or cast top and a cast bottom. the limit of the so-called return factor, in connection with which all club manufacturers will try to increase the spring properties of the striking surface. To do this, it is necessary to reduce the thickness of the impact surface and use stronger alloys for it, such as SP700, 15-3-3-3 and VT-23. Now let's focus on the use of titanium and its alloys on other sports equipment. Race bike tubes and other parts are made from ASTM Grade 9 Ti3Al-2.5V alloy. A surprisingly significant amount of titanium sheet is used in the manufacture of scuba diving knives. Most manufacturers use Ti6Al-4V alloy, but this alloy does not provide blade edge durability like other stronger alloys. Some manufacturers are switching to using BT23 alloy.

Titanium and alloys based on it are widely used in various fields. First of all, titanium alloys are widely used in the construction of various equipment due to their high corrosion resistance, mechanical strength, low density, heat resistance and many other characteristics. Considering the properties and applications of titanium, one cannot fail to note its rather high cost. However, it is fully compensated by the characteristics and durability of the material.

Titanium has a high strength and melting point, differs from other metals in durability.

Basic properties of titanium

Titanium is in group IV of the fourth period of the periodic table of chemical elements. In the most stable and most important compounds, the element is tetravalent. Externally, titanium resembles steel. It is a transition element. The melting point reaches almost 1700°, and the boiling point reaches 3300°. As for such a property as the latent heat of fusion and evaporation, for titanium it is almost 2 times higher than that for iron.

It has 2 allotropic modifications:

1. Low-temperature, which is able to exist up to a temperature of 882.5 °.
2. High temperature resistant from 882.5° to melting point.

Properties such as specific heat and density place titanium between the two materials with the widest structural uses: iron and aluminium. The mechanical strength of titanium is almost 2 times higher than that of pure iron and almost 6 times that of aluminum. However, the properties of titanium are such that it is able to absorb large amounts of hydrogen, oxygen and nitrogen, which negatively affects the plastic characteristics of the material.

The material is characterized by very low thermal conductivity. For comparison, it is 4 times higher for iron, and 12 times higher for aluminum. As for such a property as the coefficient of thermal expansion, at room temperature it has a relatively low value and increases with increasing temperature.

Titanium has low moduli of elasticity. As the temperature rises to 350°, they begin to decrease almost linearly. It is this moment that is a significant drawback of the material.

Titanium is characterized by a rather large value of electrical resistivity. It can fluctuate within a fairly wide range and depends on the content of impurities.

Titanium is a paramagnetic material. Such substances are characterized by a decrease in magnetic susceptibility during heating. However, titanium is an exception - with increasing temperature, its magnetic susceptibility increases significantly.

Applications of titanium

Titanium alloy medical instruments are characterized by high corrosion resistance, biological stability and ductility.

The properties of the material provide a fairly wide range of applications. Thus, titanium alloys are used in large volumes in the construction of ships and various equipment. The use of the material as an alloying additive to high-quality steels and as a deoxidizer has been established. Alloys with nickel have found application in engineering and medicine. Such connections have unique properties in particular, they have shape memory.

The use of compact titanium in the production of parts for electrovacuum devices used at high temperatures has been established. The properties of technical titanium make it possible to use it in the production of valves, pipelines, pumps, fittings and other products designed for operation in aggressive conditions.

Alloys are characterized by insufficient heat resistance, but have high corrosion resistance. This allows the use of various titanium-based alloys in the chemical field. For example, the material is used in the manufacture of pumps for pumping sulfuric and hydrochloric acid. To date, only alloys based on this material can be used in the production of various types of equipment for the chlorine industry.

The use of titanium in the transport industry

Alloys based on this material are used in the manufacture of armored units. And the replacement of various structural elements that are used in the transport industry can reduce fuel consumption, increase payload capacity, increase the fatigue limit of products and improve many other characteristics.

In the production of equipment for the chemical industry from titanium, the most important property is the corrosion resistance of the metal.

The material is well suited for use in railway construction. One of the main tasks that needs to be solved on the railways is related to the reduction of dead weight. The use of titanium bars and sheets can significantly reduce the total mass of the composition, reduce the size of axle boxes and necks, and save in traction.

Weight is also quite significant for trailers. The use of titanium instead of steel in the production of wheels and axles can also significantly increase the payload capacity.

The properties of the material make it possible to use it in the automotive industry. The material is characterized optimal combination strength and weight properties for exhaust gas systems and coil springs. The use of titanium and its alloys can significantly reduce the volume of exhaust gases, reduce fuel costs and expand the use of scrap and industrial waste through their remelting. The material and the alloys containing it have many advantages over other solutions used.

The main task of developing new parts and structures is to reduce their mass, on which the movement of the vehicle itself depends to one degree or another. Reducing the weight of moving components and parts makes it possible to potentially reduce fuel costs. Titanium parts have repeatedly proved their reliability. They are quite widely used in the aerospace industry and racing car designs.

The use of this material allows not only to reduce the weight of parts, but also to solve the issue of reducing the volume of exhaust gases.

The use of titanium and its alloys in the construction industry

In construction, an alloy of titanium and zinc is widely used. This alloy is characterized by high mechanical properties and corrosion resistance, high rigidity and ductility. The composition of the alloy contains up to 0.2% alloying additives that act as structure modifiers. Thanks to aluminum and copper, the required ductility is provided. In addition, the use of copper makes it possible to increase the ultimate tensile strength of the material, and the combination of chemical elements helps to reduce the coefficient of expansion. The alloy is also used for the production of long strips and sheets with good aesthetic characteristics.

Titanium is often used in space technology due to its lightness, strength and refractoriness.

Among the main qualities of an alloy of titanium with zinc, which are important specifically for construction, one can note such chemical and physical properties as high corrosion resistance, good appearance and safety for human health and environment.

The material has good plasticity, can be deep drawn without problems, which allows it to be used in roofing work. The alloy has no problems with soldering. That is why various three-dimensional structures and non-standard architectural elements such as domes and spiers are made of zinc-titanium, and not copper or galvanized steel. In solving such problems, this alloy is indispensable.

The scope of the alloy is very wide. It is used in facade and roofing works, products of various configurations and almost any complexity are made from it, it is widely used in the production of various decorative products such as gutters, ebbs, roofing ridges, etc.

This alloy has a very long service life. For more than a century, it will not require painting and frequent maintenance. repair work. Also, among the significant advantages of the material, its ability to recover should be highlighted. Insignificant damage in the form of scratches from branches, birds, etc. after a while they disappear on their own.

Requirements for building materials are becoming more and more serious and strict. Research companies in a number of countries have studied the soil around buildings built using an alloy of zinc and titanium. The research results confirmed that the material is completely safe. It has no carcinogenic properties and does not harm human health. Zinc-titanium is a non-combustible building material, which further increases safety.

Taking into account all the above positive characteristics such a building material in operation is approximately 2 times cheaper than roofing copper.

The alloy has two oxidation states. Over time, it changes color and loses its metallic luster. At first, zinc-titanium becomes light gray, and after a while it acquires a noble dark gray hue. Currently, the material is deliberately subjected to chemical aging.

The use of titanium and its alloys in medicine

Titanium is perfectly compatible with human tissue, therefore it is actively used in the field of endoprosthetics.

Titanium has found wide application in the medical field. Among the advantages that allowed him to become so popular, it should be noted high strength and resistance to corrosion. In addition, none of the patients was allergic to titanium.

Commercially pure titanium and Ti6-4Eli alloy are used in medicine. With its use, surgical instruments, various external and internal prostheses, up to heart valves, are made. Titanium is used to make wheelchairs, crutches and other devices.

A number of studies and experiments confirm the excellent biological compatibility of the material and its alloys with living human tissue. Soft and bone tissues grow together with these materials without problems. A low modulus of elasticity and a high rate of specific strength make titanium a very good material for endoprosthetics. It is noticeably lighter than tinplate, steel and cobalt-based alloys.

Thus, the properties of titanium make it possible to actively use it in a wide variety of areas - from the manufacture of pipes and roofs to medical prosthetics and the construction of spacecraft.

Titanium is the 4th most common in manufacturing, but efficient technology its extraction was developed only in the 40s of the last century. It is a silver-colored metal, characterized by a low specific gravity and unique characteristics. To analyze the degree of distribution in industry and other areas, it is necessary to voice the properties of titanium and the scope of its alloys.

Main characteristics

The metal has a low specific gravity - only 4.5 g/cm³. Anti-corrosion properties are due to a stable oxide film formed on the surface. Due to this quality, titanium does not change its properties during prolonged exposure to water, hydrochloric acid. Damaged areas do not occur due to stress, which is the main problem of steel.

In its pure form, titanium has the following qualities and characteristics:

• nominal melting point — 1660°С;
• under thermal influence +3 227 ° С boils;
• tensile strength - up to 450 MPa;
• characterized by a low elasticity index - up to 110.25 GPa;
• on the HB scale, the hardness is 103;
• the yield strength is one of the most optimal among metals - up to 380 MPa;
• thermal conductivity of pure titanium without additives - 16.791 W / m * C;
• minimum coefficient of thermal expansion;
• this element is a paramagnet.

For comparison, the strength of this material is 2 times that of pure iron and 4 times that of aluminum. Titanium also has two polymorphic phases - low-temperature and high-temperature.

For industrial needs, pure titanium is not used because of its high cost and required performance. To increase the rigidity, oxides, hybrids and nitrides are added to the composition. Rarely change the characteristics of the material to improve corrosion resistance. The main types of additives for obtaining alloys: steel, nickel, aluminum. In some cases, it performs the functions of an additional component.

Areas of use

Due to its low specific gravity and strength parameters, titanium is widely used in the aviation and space industries. It is used as the main structural material in its pure form. In special cases, by reducing the heat resistance, cheaper alloys are made. At the same time, its corrosion resistance and mechanical strength remain unchanged.

In addition, the material with titanium additives has found application in the following areas:

• Chemical industry. Its resistance to almost all aggressive media, except for organic acids, makes it possible to manufacture complex equipment with good performance repair-free service life.
• Vehicle production. The reason is the low specific gravity and mechanical strength. Frames or load-bearing structural elements are made from it.
• The medicine. Used for special purposes special alloy nitinol (titanium and nickel). Its distinguishing feature is shape memory. To reduce the burden on patients and minimize the likelihood of negative effects on the body, many medical splints and similar devices are made of titanium.
• In industry, metal is used for the manufacture of cases and individual elements of equipment.
• Titanium jewelry has a unique look and feel.

In most cases, the material is processed in the factory. But there are a number of exceptions - knowing the properties of this material, part of the work on changing appearance products and their characteristics can be made in the home workshop.

Processing Features

To give the product the desired shape, it is necessary to use special equipment - turning and milling machine. Manual cutting or milling of titanium is not possible due to its hardness. In addition to the choice of power and other characteristics of the equipment, it is necessary to choose the right cutting tools: cutters, cutters, reamers, drills, etc.

This takes into account the following nuances:

• Titanium shavings are highly flammable. It is necessary to force cooling the surface of the part and work at minimum speeds.
• The bending of the product is carried out only after the preliminary heating of the surface. Otherwise, cracks are likely to appear.
• Welding. Special conditions must be observed.

Titanium is a unique material with good performance and technical properties. But for its processing, you should know the specifics of the technology, and most importantly, safety precautions.

Element 22 (English Titanium, French Titane, German Titan) was discovered at the end of the 18th century, when the search and analysis of new minerals not yet described in the literature attracted not only chemists and mineralogists, but also amateur scientists. One such hobbyist, the English priest Gregor, found black sand mixed with fine, off-white sand in his parish in the Menachan Valley in Cornwall. Gregor dissolved a sample of sand in hydrochloric acid; at the same time, 46% of iron was released from the sand. Gregor dissolved the rest of the sample in sulfuric acid, and almost all of the substance went into solution, with the exception of 3.5% silica. After evaporation of the sulfuric acid solution, a white powder remained in the amount of 46% of the sample. Gregor considered it to be a special kind of lime, soluble in excess acid and precipitated with caustic potash. Continuing to study the powder, Gregor came to the conclusion that it was a combination of iron with some unknown metal. After consulting with his friend, the mineralogist Hawkins, Gregor published the results of his work in 1791, suggesting that the new metal be named Menachine after the valley in which the black sand had been found. Accordingly, the original mineral was named menaconite. Klaproth got acquainted with Gregor's message and, independently of him, began to analyze the mineral, known at that time as the "red Hungarian schorl" (rutile). Soon he managed to isolate from the mineral an oxide of an unknown metal, which he called titanium (Titan) by analogy with the titans - the ancient mythical inhabitants of the earth. Klaproth deliberately chose a mythological name as opposed to the names of the elements according to their properties, as suggested by Lavoisier and the Nomenclature Commission of the Paris Academy of Sciences, and which led to serious misunderstandings. Suspecting that Gregor's menachin and titanium were the same element, Klaproth made a comparative analysis of menaconite and rutile and established the identity of both elements. in Russia at the end of the 19th century. titanium was isolated from ilmenite and studied in detail from the chemical side by T.E. Lovits; however, he noted some errors in Klaproth's definitions. Electrolytically pure titanium was obtained in 1895 by Moissan. In Russian literature of the beginning of the 19th century. titanium is sometimes called titanium (Dvigubsky, 1824), and the name titanium appears there five years later.