The most indestructible metal. The hardest metal - what is it like?

Amazing metal

Nature has given humanity an amazing metal - plastic, viscous, malleable and viscous in its pure form, but becoming hard and brittle thanks to impurities of carbon, nitrogen, hydrogen, etc. This is chromium, the hardest metal, having a bluish-white color. Chromium (Cr) is a heavy, refractory, heat-resistant and corrosion-resistant metal. The Brinell hardness of chromium is 70-90 kgf/cm2, melting point is 1907°C, density is 7200 kg/m3, 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; the earth’s crust contains approximately 0.02% of it, which is a high figure. The largest deposits of chromium are found in ultramafic rocks. Ultramafic rocks are considered to be the closest in composition to the Earth's mantle. Stone 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. Chromium is supplied through food; a lack of this microelement leads to an increase in cholesterol in the blood, a decrease in growth rate, and a decrease in tissue sensitivity to insulin. In animal organisms, the chromium content is negligible - from ten thousandths to ten millionths of a percent. Plant tissues contain approximately 0.0005% of this metal, 92-95% of which is in the roots. Higher plants do not tolerate high chromium content, while in plankton its accumulation coefficient is 10,000-26,000.

The hardest metal and chromium compounds are used in industry: mainly for the smelting of chromium steels, nichrome, etc. Chrome is widely used as a decorative corrosion-resistant coating.

Harm of chromium

Some chromium compounds are toxic, for example, electroplating, alloying additives, alloys, refractories. With prolonged contact with a virulent (poisonous) chromium compound, initial signs of poisoning may appear - dryness, sore nose, sore throat, difficulty breathing. Typically, a mild degree of poisoning disappears if a person stops contacting chromium, otherwise the intoxication becomes chronic.

This process is characterized by the following symptoms - weakness, headache, dyspepsia, weight loss, dysfunction of the stomach, liver and pancreas are possible bronchial asthma, bronchitis, diffuse pneumosclerosis. If toxic chromium compounds come into contact with the skin, dermatitis and eczema may occur.

Our world is full amazing facts, which are interesting to many people. The properties of various metals are no exception. Among these elements, of which there are 94 in the world, there are the most ductile and malleable, and there are also those with high electrical conductivity or a high resistance coefficient. This article will talk about the hardest metals, as well as their unique properties.

Iridium ranks first in the list of metals that are distinguished by the greatest hardness. It was discovered at the beginning of the 19th century by the English chemist Smithson Tennant. Iridium has the following physical properties:

• has a silvery-white color;
• its melting point is 2466 o C;
• boiling point – 4428 o C;
• resistance – 5.3·10−8Ohm·m.

Because iridium is the hardest metal on the planet, it is difficult to process. But it is still used in various industrial fields. For example, it is used to make small balls that are used in pen nibs. Iridium is used to make components for space rockets, some parts for cars, and more.

Very little iridium occurs in nature. Findings of this metal are a kind of evidence that meteorites fell in the place where it was discovered. These cosmic bodies contain significant amount metal Scientists believe that our planet is also rich in iridium, but its deposits are closer to the Earth's core.

The second position on our list goes to ruthenium. The discovery of this inert silvery metal belongs to the Russian chemist Karl Klaus, which was made in 1844. This element belongs to the platinum group. It is a rare metal. Scientists have been able to establish that there is approximately 5 thousand tons of ruthenium on the planet. It is possible to extract approximately 18 tons of metal per year.

Due to its limited quantity and high cost, ruthenium is rarely used in industry. It is used in the following cases:

• it's not a large number of added to titanium to improve corrosion properties;
• Its alloy with platinum is used to make electrical contacts that differ high durability;
• ruthenium is often used as a catalyst for chemical reactions.

A metal called tantalum, discovered in 1802, takes third place on our list. It was discovered by the Swedish chemist A. G. Ekeberg. For a long time it was believed that tantalum is identical to niobium. But the German chemist Heinrich Rose managed to prove that these are two different element. Scientist Werner Bolton from Germany was able to isolate tantalum in its pure form in 1922. This is a very rare metal. The largest deposits of tantalum ore were discovered in Western Australia.

Due to its unique properties, tantalum is a highly sought-after metal. It is used in various fields:

• in medicine, tantalum is used to make wire and other elements that can hold tissue together and even act as a bone substitute;
• alloys with this metal are resistant to aggressive environments, which is why they are used in the manufacture of aerospace equipment and electronics;
• tantalum is also used to create energy in nuclear reactors;
• element is widely used in chemical industry.

Chromium is one of the hardest metals. It was discovered in Russia in 1763 in a deposit in the Northern Urals. It has a bluish-white color, although there are cases where it is considered a black metal. Chrome cannot be called a rare metal. The following countries are rich in its deposits:

• Kazakhstan;
• Russia;
• Madagascar;
• Zimbabwe.

There are chromium deposits in other countries as well. This metal is widely used in various branches of metallurgy, science, mechanical engineering and others.

The fifth position in the list of the hardest metals goes to beryllium. Its discovery belongs to the chemist Louis Nicolas Vauquelin from France, which was made in 1798. This metal has a silvery-white color. Despite its hardness, beryllium is a brittle material, which makes it very difficult to process. It is used to create high-quality loudspeakers. It is used to create jet fuel and refractory materials. The metal is widely used in the creation of aerospace technology and laser systems. It is also used in nuclear energy and in the manufacture of X-ray equipment.

The list of the hardest metals also includes osmium. It is an element belonging to the platinum group, and its properties are similar to iridium. This refractory metal is resistant to aggressive environments, has a high density, and is difficult to process. It was discovered by the scientist Smithson Tennant from England in 1803. This metal is widely used in medicine. Elements of pacemakers are made from it, and it is also used to create the pulmonary valve. It is also widely used in the chemical industry and for military purposes.

The transition silver metal rhenium takes the seventh position on our list. The assumption about the existence of this element was made by D.I. Mendeleev in 1871, and chemists from Germany managed to discover it in 1925. Just 5 years after this, it was possible to establish the extraction of this rare, durable and refractory metal. At that time, it was possible to obtain 120 kg of rhenium per year. Now the amount of annual metal production has increased to 40 tons. It is used for the production of catalysts. It is also used to make electrical contacts that can self-clean.

Silver-gray tungsten is not only one of the hardest metals, it also leads in refractoriness. It can only be melted at a temperature of 3422 o C. Thanks to this property, it is used to create incandescent elements. Alloys made from this element have high strength and are often used for military purposes. Tungsten is also used to produce surgical instruments. It is also used to make containers in which radioactive materials are stored.

One of the hardest metals is uranium. It was discovered in 1840 by the chemist Peligo. D.I. Mendeleev made a great contribution to the study of the properties of this metal. The radioactive properties of uranium were discovered by the scientist A. A. Becquerel in 1896. Then a chemist from France called the detected metal radiation Becquerel rays. Uranium is often found in nature. The countries with the largest deposits of uranium ore are Australia, Kazakhstan and Russia.

The final place in the top ten hardest metals goes to titanium. For the first time this element was obtained in its pure form by the chemist J. Ya. Berzelius from Sweden in 1825. Titanium is a lightweight silver-white metal that is highly durable and resistant to corrosion and mechanical stress. Titanium alloys are used in many branches of mechanical engineering, medicine and the chemical industry.

Use of metals in Everyday life began at the dawn of human development, and the first metal was copper, since it is available in nature and can be easily processed. No wonder archaeologists during excavations find various products and household utensils made of this metal. In the process of evolution, people gradually learned to connect various metals, obtaining increasingly durable alloys suitable for the manufacture of tools, and later weapons. Nowadays, experiments continue, thanks to which it is possible to identify the strongest metals in the world.

• high specific strength;
• resistance to high temperatures;
• low density;
• corrosion resistance;
• mechanical and chemical resistance.

Titanium is used in the military industry, aviation medicine, shipbuilding, and other areas of production.

The most famous element, which is considered one of the most durable metals in the world, and under normal conditions is a weak radioactive metal. In nature, it is found both in a free state and in acidic sedimentary rocks. It is quite heavy, widely distributed everywhere and has paramagnetic properties, flexibility, malleability, and relative ductility. Uranium is used in many areas of production.

Known as the most refractory metal in existence, it is one of the strongest metals in the world. It is a solid transitional element of a shiny silver-gray color. It has high strength, excellent refractoriness, and resistance to chemical influences. Due to its properties, it can be forged and drawn into a thin thread. Known as tungsten filament.

Among representatives of this group it is considered a transition metal high density silver-white color. It occurs in nature in its pure form, but is found in molybdenum and copper raw materials. It is characterized by high hardness and density, and has excellent refractoriness. It has increased strength, which is not lost due to repeated temperature changes. Rhenium is an expensive metal and has high cost. Used in modern technology and electronics.

A shiny silver-white metal with a slightly bluish tint, it belongs to the platinum group and is considered one of the strongest metals in the world. Similar to iridium, it has a high atomic density, high strength and hardness. Since osmium is a platinum metal, it has properties similar to iridium: refractoriness, hardness, brittleness, resistance to mechanical stress, as well as to the influence of aggressive environments. It is widely used in surgery, electron microscopy, the chemical industry, rocketry, and electronic equipment.

Belongs to the group of metals and is an element light gray, having relative hardness and high toxicity. Due to its unique properties, beryllium is used in a wide variety of production areas:

• nuclear energy;
• aerospace engineering;
• metallurgy;
• laser technology;
• nuclear energy.

Due to its high hardness, beryllium is used in the production of alloying alloys and refractory materials.

Next on the list of the ten strongest metals in the world is chromium - a hard, high-strength metal of a bluish-white color, resistant to alkalis and acids. It occurs in nature in its pure form and is widely used in various branches of science, technology and production. Chromium is used to create various alloys that are used in the manufacture of medical and chemical processing equipment. When combined with iron, it forms an alloy called ferrochrome, which is used in the manufacture of metal-cutting tools.

Tantalum deserves bronze in the ranking, as it is one of the strongest metals in the world. It is a silvery metal with high hardness and atomic density. Due to the formation of an oxide film on its surface, it has a leaden tint.

The distinctive properties of tantalum are high strength, refractoriness, resistance to corrosion, and resistance to aggressive environments. The metal is a fairly ductile metal and can be easily machining. Today tantalum is successfully used:

• in the chemical industry;
• during the construction of nuclear reactors;
• in metallurgical production;
• when creating heat-resistant alloys.

The second place in the ranking of the most durable metals in the world is occupied by ruthenium, a silvery metal belonging to the platinum group. Its peculiarity is the presence of living organisms in the muscle tissue. Valuable properties of ruthenium are high strength, hardness, refractoriness, chemical resistance, and the ability to form complex compounds. Ruthenium is considered a catalyst for many chemical reactions and acts as a material for the manufacture of electrodes, contacts, and sharp tips.

The ranking of the most durable metals in the world is headed by iridium - a silver-white, hard and refractory metal that belongs to the platinum group. In nature, the high-strength element is extremely rare and is often combined with osmium. Due to its natural hardness, it is difficult to machine and is highly resistant to chemicals. Iridium reacts with great difficulty to exposure to halogens and sodium peroxide.

This metal plays an important role in everyday life. It is added to titanium, chromium and tungsten to improve resistance to acidic environments, and is used in the manufacture stationery, used in jewelry to create jewelry. The cost of iridium remains high due to its limited presence in nature.

Most of the elements in the periodic table belong 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, with one exception to this rule: mercury. Chromium is considered the hardest metal.

In 1766, a previously unknown rich red mineral was discovered at one of the mines near Yekaterinburg. It was given the name “Siberian red lead”. Modern name This one is “crocoite”, its PbCrO4. The new mineral has attracted the attention of scientists. In 1797, the French chemist Vauquelin, conducting experiments with it, isolated a new metal, later called chromium.

Chromium compounds are brightly colored in a variety of colors. This is why it got its name, because in translation from Greek “chrome” means “paint”.

In its pure form, it is a silver-bluish metal. It is an essential component of alloy (stainless) steels, giving them corrosion resistance and hardness. Chrome is widely used in electroplating to produce beautiful and wear-resistant protective coating, as well as in leather processing. Rocket parts, heat-resistant nozzles, etc. are made from alloys based on the base. Most sources claim that chromium is the most hard metal of all those existing on . The hardness of chromium (depending on the experimental conditions) reaches 700-800 units on the Brinell scale.

Although chromium is considered the hardest metal on earth, it is only slightly inferior in hardness to tungsten and uranium.

How chromium is obtained in industry

Chromium is found in many minerals. The richest deposits of chrome ores are located in South Africa (South Africa). There are many chrome ores in Kazakhstan, Russia, Zimbabwe, Turkey and some other countries. The most widespread is chromium iron ore Fe (CrO2)2. From this mineral, chromium is obtained by firing in electric furnaces over a layer. The reaction proceeds according to the following formula: Fe (CrO2)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 fused with calcined