The hardest metal in the world (Titanium, Chromium and Tungsten). The heaviest metals in the world
many lovers interesting facts I'm wondering which metal is the hardest? And offhand to answer this question will not be easy. Of course, any chemistry teacher can easily say correctly without even thinking. But among ordinary citizens who last time studied chemistry at school, not many will be able to correctly and quickly give an answer. This is due to the fact that everyone has been accustomed to making various toys from wire since childhood and remembered well that copper and aluminum are soft and easy to bend, but steel, on the contrary, is not so easy to give the desired shape. A person deals with the three named metals most often, so he does not even consider the rest of the candidates. But steel is certainly not the hardest metal in the world. In fairness, it should be noted that this is not a metal at all in the chemical sense, but a compound of iron with carbon.
What is titanium?
The hardest metal is titanium. Pure titanium was first obtained in 1925. This discovery made a splash in scientific circles. Industrialists immediately drew attention to the new material and appreciated the benefits of its use. By official version, most solid metal on Earth got its name in honor of the indestructible Titans, which, according to ancient Greek mythology were the founders of the world.
According to scientists, the total world reserves of titanium today are about 730 million tons. At the current rate of extraction of fossil raw materials, there will be enough for another 150 years. Titanium ranks 10th in terms of natural reserves among all known metals. The world's largest titanium producer is the Russian company VSMPO-Avisma, which satisfies up to 35% of the world's needs. The company is engaged in a full cycle of processing from ore mining to the manufacture of various products. It occupies about 90% of the Russian titanium production market. About 70% finished products goes for export.
Titanium is a light, silvery metal with a melting point of 1670 degrees Celsius. Shows high chemical activity only when heated, in normal conditions does not react with most chemical elements and compounds. It does not occur in nature in its pure form. It is common in the form of rutile (titanium dioxide) and ilmenite (a complex substance consisting of titanium dioxide and ferrous oxide) ores. Pure titanium is recovered by sintering the ore with chlorine and then displacing the more active metal (most commonly magnesium) from the resulting tetrachloride.
Industrial applications of titanium
The hardest metal has a fairly wide range of applications in many industries. Amorphously arranged atoms provide titanium the highest level tensile and torsion strength, good impact resistance, high magnetic qualities. The metal is used to make air transport hulls and missiles. It copes well with the enormous loads that machines experience at great heights. Titanium is also used in the manufacture of hulls for submarines, as it is able to withstand high pressure at great depths.
In the medical industry, metal is used in the manufacture of prostheses and dental implants, as well as surgical instruments. As an alloying element, the element is added to some steel grades, which gives them increased strength and corrosion resistance. Titanium is well suited for casting, as it allows you to get perfectly smooth surfaces. It is also made from Jewelry and decorative items. Titanium compounds are also actively used. Paints, white are made from dioxide, they are added to the composition of paper and plastic.
Complex organic titanium salts are used as a hardening catalyst in paint and varnish production. Titanium carbide is used to make various tools and attachments for processing and drilling other metals. In precision engineering, titanium aluminide is used to produce wear-resistant elements that have a high margin of safety.
The hardest metal alloy was obtained by American scientists in 2011. It consists of palladium, silicon, phosphorus, germanium and silver. new material called "metal glass". He combined the hardness of glass and the plasticity of metal. The latter does not allow cracks to propagate, as happens with standard glass. Naturally, the material was not put into wide production, since its components, especially palladium, are rare metals and are very expensive.
IN this moment the efforts of scientists are aimed at searching for alternative components that would preserve the obtained properties, but significantly reduce the cost of production. However, individual parts for the aerospace industry are already being produced from the resulting alloy. If alternative elements can be introduced into the structure and the material becomes widespread, then it is quite possible that it will become one of the most demanded alloys of the future.
Because they have the highest density. Among them, the heaviest are osmium and iridium. This The density index of these metals is almost the same, except for a slight calculation error.
Iridium was discovered in 1803. It was discovered by the English chemist Smithson Tennat, while examining natural platinum delivered from South America. Translated from the ancient Greek, the name "iridium" means "rainbow".
Scientific interest as a source electrical energy represents the heavy metal isotope - iridium-192m2, since this metal is very large - 241 years. Iridium has found wide application in industry and paleontology - it is used for the production of nibs for pens, determining the age of the layers of the earth.
The discovery of osmium happened by accident in 1804. This hardest metal has been found in chemical composition sediment of platinum dissolved in aqua regia. The name "osmium" comes from the ancient Greek word for "smell". This metal is almost non-existent in nature. Most often it is found in the composition. Like iridium, osmium is almost not subject to mechanical stress. One liter of osmium is much heavier than ten liters of water. But this property of this metal has not yet found application anywhere.
The hardest metal, osmium, is mined in Russian and American mines. However, South Africa is recognized as the richest of its deposits. Osmium is often found in iron meteorites.
Of particular interest is osmium-187, which is exported only by Kazakhstan. It is used to determine the age of meteorites. One gram of this isotope costs 10,000 US dollars.
In industry, the hard alloy of osmium with tungsten (osram) is mainly used for the production of incandescent lamps. Osmium is also a catalytic agent in the production. Rarely enough, cutting parts for instruments in surgery are made from this metal.
Both heavy metals - osmium and iridium - are almost always contained in the same alloy. This is a certain pattern. And to separate them, you need to make a lot of effort, because they are not as soft as, for example, silver.
amazing metal
Nature gave humanity an amazing metal - ductile, ductile, malleable and malleable in its pure form, but becoming hard and brittle due to impurities of carbon, nitrogen, hydrogen, etc. It is chromium, the hardest metal, having a bluish-white color. Chromium (Cr) is a heavy, refractory, heat-resistant and corrosion-resistant metal. The hardness of chromium according to Brinell is 70-90 kgf/cm2, the melting point is 1907°C, the density is 7200 kg/m3, the boiling point is 2671°C.
Usually the hardest metal occurs in nature in the form of chromium iron ore. Chromium is a fairly common element in earth's crust it contains approximately 0.02%, which is a high figure. The largest deposits chromium are in the ultrabasic rocks. Ultramafic rocks are considered to be closest in composition to the Earth's mantle. Stony meteorites are also rich in chromium. In water, the content of this metal is very low - only 0.00005 mg / l.
Nutrient
Chromium is a biogenic substance and is part of the tissues of living organisms. The intake of chromium occurs with food, the lack of this trace element leads to an increase in cholesterol in the blood, a decrease in the growth rate, and a decrease in the sensitivity of tissues to insulin. In animal organisms, the content of chromium is negligible - from ten thousandths to ten millionths of a percent. The plant tissues of this metal contain approximately 0.0005%, 92-95% of which are in the roots. higher plants do not tolerate high chromium content, while plankton have a coefficient of its accumulation of 10,000-26,000.
The hardest metal and chromium compounds are used in industry: mainly for the smelting of chromium steels, nichrome, etc. Chromium is widely used as a decorative corrosion-resistant coating.
The harm of chromium
Some chromium compounds are toxic, such as electroplating, alloying additives, alloys, refractories. With prolonged contact with a virulent (poisonous) chromium compound, initial signs poisoning - dryness, pain in the nose, sore throat, shortness of breath. Usually, a mild degree of poisoning disappears if a person stops contacting with chromium, otherwise intoxication passes into a chronic stage.
This process is characterized by the following signs - weakness, headache, dyspepsia, weight loss, dysfunction of the stomach, liver and pancreas, bronchial asthma, bronchitis, diffuse pneumosclerosis are possible. If toxic chromium compounds get on the skin, dermatitis and eczema may appear.
Most of the elements of the periodic table refers to metals. They differ in physical and chemical characteristics, but have general properties: high electrical and thermal conductivity, plasticity, positive temperature. Most metals are solid under normal conditions, there is one exception to this rule - mercury. Chromium is considered the hardest metal.
In 1766, at one of the mines near Yekaterinburg, a previously unknown mineral of saturated red color was discovered. He was given the name "Siberian red lead". The modern name for this is "crocoite", its PbCrO4. The new mineral attracted the attention of scientists. In 1797, the French chemist Vauquelin, conducting experiments with him, isolated a new metal, later called chromium.
Chromium compounds have a bright color of various colors. For this, he got his name, because in Greek "chromium" means "paint".
In its pure form, it is a bluish-silver metal. It is the most important component of alloyed (stainless) steels, giving them corrosion resistance and hardness. Chromium is widely used in electroplating, for applying a beautiful and wear-resistant protective coating, as well as in leather processing. Base alloys are used to make rocket parts, heat-resistant nozzles, etc. Most sources state that chromium is the hardest metal of all that exists on. The hardness of chromium (depending on the experimental conditions) reaches 700-800 units on the Brinell scale.
Chromium, although considered the hardest metal on earth, is only slightly inferior in hardness to tungsten and uranium.
How is chromium obtained in industry
Chromium is part of many minerals. The richest deposits of chrome ores are located in South Africa (Republic of South Africa). There are many chrome ores in Kazakhstan, Russia, Zimbabwe, Turkey and some other countries. Chromium iron ore Fe (CrO2) 2 is the most widespread. From this mineral, chromium is obtained by roasting in electric furnaces over a layer. The reaction proceeds according to the following formula: Fe (CrО2) 2 + 4C = 2Cr + Fe + 4CO.
The hardest metal from chromium iron ore can be obtained in another way. To do this, first the mineral is alloyed with calcined
If strength is commonly understood as the ability of solid bodies to resist destruction and retain the shape of the product, then the following metals can be attributed to heavy-duty and durable metals.
Name titanium was awarded by Martin Klaproth, a German researcher who discovered a new metal not according to his chemical qualities, and in honor of the mythological heroes of the children of the earth - the titans.
The presence of titanium in nature is in 10th place, most of all it is concentrated in minerals. Without this metal it would be impossible latest discoveries in the field of rocket, ship and aircraft construction. Titanium is used in all areas of industry, in the manufacture of medical implants and body armor with Food Industry and agriculture.
2nd place 
Light gray tungsten , literally translated as wolf cream, is the most refractory metal, so it is indispensable in the manufacture of heat-resistant surfaces and products. The filament in a conventional light bulb is made from a tungsten filament.
That metal is used in ballistic missiles, in the manufacture of shells and bullets, in gyroscopic ultra-high-speed rotors.
3rd place 
Tantalum it is almost impossible to modify, because it begins to melt at a temperature of 3015 degrees Celsius, and boils at a boiling point of 5300 degrees. It is impossible for an ordinary person to even imagine such a heat. The bluish-gray metal is the most indispensable in modern medicine, wire and sheets are made from it, with which damaged bones are covered.
Opened in 1817 molybdenum, gray-steel metal in its pure form is practically not found. The infusibility of this metal is striking, the melting point of which exceeds 2620 degrees. Molybdenum has found the greatest use in the military industry, where gun and armor steels are made.
5th place 
Aviation and mechanical engineering, nuclear power and astronautics use niobium, very similar in its properties to tantalum metal. Niobium is practically not affected by any substances, neither salts nor acids, it is difficult to melt, and difficult to oxidize, which is what makes the unique metal so popular.
6th place 
The heaviest metal on earth iridium possesses the most persistent anti-corrosion properties, even aqua regia cannot melt it. The addition of iridium to other alloys enhances their ability to resist corrosion.
7th place 
Beryllium is one of the rare metals that are mined in the earth. Its unique qualities, such as high thermal conductivity and fire resistance, have made this metal indispensable in the manufacture of nuclear reactors. Beryllium alloys rightfully occupy a leading position in the aerospace and aviation industries.
8th place 
Light blue chrome , which is also one of the most durable metals due to its unique properties when added to steel alloys, it makes them harder and more corrosion resistant. Chrome parts have a beautiful appearance which does not change over time.
9th place 
The Saxons take care of their legends, the name of the hero of one of them, Kobold, was immortalized in the name of the metal - cobalt . Very often, when extracting ore, seekers mistook the gray-pink metal for silver.
Refractory metal, as an additive, increases the heat resistance, hardness and wear resistance of steel. Due to its unique qualities, cobalt is indispensable in machine tools.
Hafnium - a metal of light gray color, unique in its qualities, is mined from zirconium ore. Solid, refractory hafnium has a unique feature, the fact is that its heat-capacity dependence is anomalous and does not fall under any laws of physics.
Hafnium is used in nuclear power engineering and in optics, to strengthen various alloys and to make glass for X-rays; it is difficult to imagine military production without it.
