Presentation on the topic: Copper and its alloys. Presentation, report Copper and its alloys Copper and copper alloys presentation

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Presentation on the topic: Copper and its alloys

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History of copper. Copper has been known since time immemorial and is one of the "magnificent seven" of the most ancient metals used by mankind - these are gold, silver, copper, iron, tin, lead and mercury. According to archaeological data, copper was known to people already 600 years ago. It turned out to be the first metal that replaced stone in ancient man's primitive tools. This was the beginning of the so-called. copper age, which lasted about 2000 years. Axes, knives, maces, household items were forged from copper, and then smelted. According to legend, the ancient blacksmith god Hephaestus forged a shield of pure copper for the invincible Achilles. Stones for the 147-meter pyramid of Cheops.

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Now it is impossible to establish when It is impossible to establish now when man first became acquainted with copper. In any case, around 3000 BC. e. the Egyptians could already make wire out of it. In nature, copper is sometimes found in its native state, and this made it easier for the ancient craftsmen to extract it. They knew how to forge various products from this metal with stone tools. Later, copper mines began to be developed, which were scattered all over the planet: and in North America on the shores of the Great Lakes, and in Asia on the Sinai Peninsula, and in Europe on the territory of present-day Austria, and on the island of Cyprus. According to experts, the Latin name for the metal "cuprum" comes from the name of this island. The name of the metal familiar to the Russian ear - "copper", probably came from the Old Slavonic "smid", which meant metal in general.

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The use of copper. Copper has long been used in construction: the ancient Egyptians built copper water pipes; the roofs of medieval castles and churches were covered with sheet copper, for example, the famous royal castle in Elsinore (Denmark) is covered with roofing copper. Coins and jewelry were made from copper. Due to its low electrical resistance, copper is the main metal of electrical engineering: more than half of all copper produced is used to produce electrical wires for high-voltage transmissions and low-current cables. Even insignificant impurities in copper lead to an increase in its electrical resistance and large losses of electricity. Ship hulls are sheathed with copper tin. High thermal conductivity and corrosion resistance make it possible to manufacture parts of heat exchangers, refrigerators, vacuum apparatuses, pipelines for pumping oils and fuels, etc. from copper. Copper is also widely used in electroplating when applying protective coatings to steel products. So, for example, when nickel-plating or chromium-plating of steel objects, copper is pre-deposited on them; in this case, the protective coating lasts longer and is more effective. Copper is also used in electroforming (i.e., when replicating products by obtaining their mirror image), for example, in the manufacture of metal matrices for printing banknotes, and in the reproduction of sculptural products.

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Bronze products were in use Bronze products were used by the ancient Egyptians, Assyrians, Etruscans. Beautiful bronze statues were cast in Greece and Rome; many of them have survived to this day, such as the famous equestrian statue of Marcus Aurelius in Rome or one of the seven wonders of the world, the Colossus of Rhodes. For sculptures standing outdoors, especially in places with a humid climate, bronze is preferable because over time a dense greenish-brown patina appears on its surface, which protects the metal from further oxidation. The shields of Roman legionnaires were also bound with bronze.

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The Bronze Horseman sung by A. S. Pushkin in St. Petersburg and the monument to Minin and Pozharsky on Red Square in Moscow were cast from bronze. Due to its special mechanical properties and good casting qualities, bronze is an ideal metal for casting bells with a loud and beautiful sound. Everyone knows the giant "Tsar Bell" in the Moscow Kremlin weighing almost 202 tons, cast in 1733-1735 by Russian masters I.F. and M.F. Matronin. Guns were also made of bronze in the old days; the largest of them "Tsar Cannon" (39.3 tons) was intended for the defense of the Moscow Kremlin and was cast by master A. Chokhov in 1586.

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And now sculptures are cast from bronze, And now sculptures are cast from bronze, chandeliers, candelabra, candlesticks, as well as parts of various mechanisms (for example, bearings) are made. As many centuries ago, to obtain bronze, copper and copper scrap are alloyed with tin. Only not in earthen, but in modern electric furnaces. So that copper and tin do not oxidize during melting, and bronze is especially durable, phosphorus compounds are added to the charge before casting. Due to the shortage of tin and its high price, tin bronze is gradually being replaced by other bronzes, ch. arr. aluminum. Aluminum bronze containing up to 11% Al has good mechanical properties, is stable in sea water and even in dilute hydrochloric acid. This very strong alloy is used for the manufacture of pipelines, parts of steam turbines and aircraft engines, etc. "Copper" coins were minted from aluminum bronze in Russia from 1926 to 1957. Bearings for diesel locomotives, ship engines, water turbines are made from lead bronze. Beryllium bronze is extremely strong and durable, which, due to its elastic properties, serves as a material for springs that practically do not know fatigue (withstand up to 20 million load cycles).

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Brass. Brass is an alloy of copper and zinc. Although zinc was discovered only in the Middle Ages, brass was known to the ancient Romans, who obtained it by smelting copper ores with zinc without air. To give brass the desired properties, alloying metals such as Al, Mn, Ni, Fe, etc. are often introduced into its composition in small quantities. Brass melts more easily than copper, but it is harder than it. Brass is well forged, pierced into sheets, stamped, drawn into wire and perfectly polished (up to mirror shine). Products from it can be hardened. If necessary, brass can be applied to the surface of other metals by the electrochemical method. It is important that brass is much cheaper than copper. Brass is used in mechanical engineering and electrical engineering; parts of various mechanisms, water and gas taps, radiator pipes, door handles, hinges, cartridge cases are made from it. Brass with aluminum addition appearance similar to gold, badges, emblems, medals are made from it. If there is relatively little zinc in the alloy (up to 18%), brasses have a reddish tint. For example, brass with up to 10% zinc is called tombac; From this alloy, from 1961 to 1991, “copper” coins were minted in Russia, in denominations from 1 to 5 kopecks. Alloys with a high zinc content (up to 50%) are yellow and are called brass proper. They are perfectly processed by rolling, pressing and broaching, and good quality castings are obtained from them.

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other alloys. Of other alloys, we note monel metal (50 - 70% copper, 15 - 25% nickel and zinc with the addition of lead, tin and iron) was previously used for the manufacture of cutlery and jewelry "under silver". Due to its high corrosion resistance and strength, good plasticity, it is now used in the chemical, shipbuilding, medical, oil, textile and other industries. But constantan, manganin, chromel and kopel almost do not change their resistance with significant temperature fluctuations and therefore faithfully serve in electrical engineering for the manufacture of thermocouples - very sensitive devices that measure temperature. Also compensating wires, rheostats, parts of heating devices are made from chromel and kopel. Reference resistors and elements of measuring instruments are made from mangonin.

Introduction. It just so happened that in one subgroup were copper, silver and gold: elements of the same age as civilization. All of them at different times acted as the ultimate measure of values, in other words, money. Weapons were forged from these metals, household utensils and jewelry were made. Today, copper, silver and gold are in the thick of technological progress. The physicist will emphasize their unsurpassed heat and electrical conductivity. The sculptor will note the plasticity and beautiful appearance. He will be supported by a jeweler and chaser, and a chemist will certainly remember the noble inertness and high corrosion resistance of these metals. Golden mask of Pharaoh Tutankhamun. Gold nugget "Mephistopheles" weighing 20.25 g, found in Siberia. Diamond fund. Moscow. Silver nugget Cap of Monomakh. Boctok, late 13th early 14th century Bowl. Ancient Russia Chernihiv, 12th century Silver; forging, carving. Belonged to Prince Vladimir Davydovich of Chernigov.

Now it is impossible to establish when man first became acquainted with copper. In any case, around 3000 BC. e. the Egyptians could already make wire out of it. In nature, copper is sometimes found in its native state, and this made it easier for the ancient craftsmen to extract it. They knew how to forge various products from this metal with stone tools. Later, copper mines began to be developed, which were scattered all over the planet: in North America on the shores of the Great Lakes, and in Asia on the Sinai Peninsula, and in Europe on the territory of present-day Austria, and on the island of Cyprus. According to experts, the Latin name for the metal "cuprum" comes from the name of this island. The name of the metal familiar to the Russian ear - "copper", probably came from the Old Slavonic "smith", which meant metal in general. Nugget of copper.

Bronze. June Bronze Weapons in China. Ancient metallurgists learned how to extract copper from ores and add additives to it that improve the properties of the alloy. So, mixing copper with tin, they got bronze. It was such an important stage in human history that we call it Bronze Age. An unusually simple way to obtain an alloy (a fire melts a mixture of tin and copper) allowed craftsmen to make various tools, tools and, of course, weapons from it. Bronze is harder than copper, stable in air, well processed into various products, but more fusible. The ancient Greeks, the inhabitants of Mesopotamia, and Japanese craftsmen were able to obtain especially high-quality alloys. Therefore, it is not at all accidental that the rise and fall of states were directly related to the degree of development of metallurgy.

Bronze items were used by the ancient Egyptians, Assyrians, and Etruscans. Beautiful bronze statues were cast in Greece and Rome; many of them have survived to this day, such as the famous equestrian statue of Marcus Aurelius in Rome or one of the seven wonders of the world, the Colossus of Rhodes. For sculptures standing outdoors, especially in places with a humid climate, bronze is preferable because over time a dense greenish-brown patina appears on its surface, which protects the metal from further oxidation. The shields of Roman legionnaires were also bound with bronze. Shield of a Roman legionnaire.

It is from bronze that the "Bronze Horseman" sung by A. S. Pushkin in St. Petersburg and the monument to Minin and Pozharsky on Red Square in Moscow were cast. Due to its special mechanical properties and good casting qualities, bronze is an ideal metal for casting bells with a loud and beautiful sound. Everyone knows the giant "Tsar Bell" in the Moscow Kremlin weighing almost 202 tons, cast in years by Russian masters I.F. and M.F. Matronin. Guns were also made of bronze in the old days; the largest of them "Tsar Cannon" (39.3 tons) was intended for the defense of the Moscow Kremlin and was cast by master A. Chokhov in 1586 by E. M. Falcone. "Bronze Horseman". Saint Petersburg. The Tsar Bell was cast by order of Empress Anna Ioannovna in the years. Moscow casters Ivan Motorin and his son Mikhail instead of the Great Assumption Bell that crashed in the city during a fire.

Tsar Cannon. Master Andrey Chokhov. The monument to the tradesman Kuzma Minin and Prince Dmitry Pozharsky was created according to the project of the artist I.P. Martos and cast from bronze by the foundry master of the Academy of Arts V.P. Ekimov, opened on February 20, 1818.

And now sculptures are cast from bronze, chandeliers, candelabra, candlesticks, as well as parts of various mechanisms (for example, bearings) are made. As many centuries ago, to obtain bronze, copper and copper scrap are alloyed with tin. Only not in earthen, but in modern electric furnaces. So that copper and tin do not oxidize during melting, and bronze is especially durable, phosphorus compounds are added to the charge before casting. Due to the shortage of tin and its high price, tin bronze is gradually being replaced by other bronzes, ch. arr. aluminum. Aluminum bronze containing up to 11% Al has good mechanical properties, is stable in sea water and even in dilute hydrochloric acid. This very strong alloy is used for the manufacture of pipelines, parts of steam turbines and aircraft engines, etc. "Copper" coins were minted from aluminum bronze in Russia from 1926 to 1957. Bearings for diesel locomotives, ship engines, water turbines are made from lead bronze. Beryllium bronze is extremely strong and durable, which, due to its elastic properties, serves as a material for springs that practically do not know fatigue (withstand up to 20 million load cycles). Saint Petersburg. Bronze monument to Ostap Bender on Italian street. Sculptor Albert Charkin.

Brass. Brass is an alloy of copper and zinc. Although zinc was discovered only in the Middle Ages, brass was known to the ancient Romans, who obtained it by smelting copper ores with zinc without air. To give brass the desired properties, alloying metals such as Al, Mn, Ni, Fe, etc. are often introduced into its composition in small quantities. Brass melts more easily than copper, but it is harder than it. Brass is well forged, pierced into sheets, stamped, drawn into wire and perfectly polished (to a mirror finish). Products from it can be hardened. If necessary, brass can be applied to the surface of other metals by the electrochemical method. It is important that brass is much cheaper than copper. Brass is used in mechanical engineering and electrical engineering; parts of various mechanisms, water and gas taps, radiator pipes, door handles, hinges, cartridge cases are made from it. Brass with the addition of aluminum is similar in appearance to gold; badges, emblems, and medals are made from it. If there is relatively little zinc in the alloy (up to 18%), brasses have a reddish tint. For example, brass with up to 10% zinc is called tombac; From this alloy, from 1961 to 1991, “copper” coins were minted in Russia, in denominations from 1 to 5 kopecks. Alloys with a high zinc content (up to 50%) are yellow and are called brass proper. They are perfectly processed by rolling, pressing and broaching, and good quality castings are obtained from them.

other alloys. Of other alloys, we note monel metal (% copper,% nickel and zinc with the addition of lead, tin and iron) was previously used for the manufacture of cutlery and jewelry "under silver". Due to its high corrosion resistance and strength, good plasticity, it is now used in the chemical, shipbuilding, medical, oil, textile and other industries. But constantan, manganin, chromel and kopel almost do not change their resistance with significant temperature fluctuations and therefore faithfully serve in electrical engineering for the manufacture of thermocouples - very sensitive devices that measure temperature. Also compensating wires, rheostats, parts of heating devices are made from chromel and kopel. Reference resistors and elements of measuring instruments are made from mangonin.

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Now it is impossible to establish when It is impossible to establish now when man first became acquainted with copper. In any case, around 3000 BC. e. the Egyptians could already make wire out of it. In nature, copper is sometimes found in its native state, and this made it easier for the ancient craftsmen to extract it. They knew how to forge various products from this metal with stone tools. Later, copper mines began to be developed, which were scattered all over the planet: in North America on the shores of the Great Lakes, and in Asia on the Sinai Peninsula, and in Europe on the territory of present-day Austria, and on the island of Cyprus. According to experts, the Latin name for the metal "cuprum" comes from the name of this island. The name of the metal familiar to the Russian ear - "copper", probably came from the Old Slavonic "smid", which meant metal in general.

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The Bronze Horseman, sung by Pushkin in St. Petersburg, and the monument to Minin and Pozharsky on Red Square in Moscow were cast from bronze. Due to its special mechanical properties and good casting qualities, bronze is an ideal metal for casting bells with a loud and beautiful sound. Everyone knows the giant "Tsar Bell" in the Moscow Kremlin weighing almost 202 tons, cast in 1733-1735 by Russian masters I.F. and M.F. Matronin. Guns were also made of bronze in the old days; the largest of them "Tsar Cannon" (39.3 tons) was intended for the defense of the Moscow Kremlin and was cast by master A. Chokhov in 1586.

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Copper is a heavy rose-red metal, soft and malleable, its melting point is 1083°C, and is an excellent conductor. electric current and heat, the electrical conductivity of copper is 1.7 times higher than that of aluminum, and 6 times higher than iron. In everyday life, we always have to deal with copper and its alloys: we turn on a computer or a table lamp - current flows through copper wires, we use metal money, which, both yellow and white, are made of copper alloys. Some houses are decorated with bronze items, utensils are made of copper. Meanwhile, copper is far from the most common element in nature: the copper content in the earth's crust is 0.01%, which allows it to occupy only 23rd place among all elements.

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Copper is the first metal that was first used by man in antiquity, several millennia BC. The first copper tools were made from native copper, which is quite common. The largest copper nugget was found in the United States, it had a mass of 420 tons. But in view of the fact that copper is a soft metal, copper in ancient times could not displace stone tools. Only when man learned to melt copper and invented bronze (an alloy of copper and tin) did metal replace stone. The widespread use of copper began in the 4th millennium BC. e. Copper is an inactive metal; in the electrochemical series of voltages, it is to the right of hydrogen. It does not interact with water, alkali solutions, hydrochloric and dilute sulfuric acid. However, in acids - strong oxidizing agents (for example, nitric and concentrated sulfuric) - copper dissolves: Cu + 4HMO3 - Cu (NO3) 2 + 2NO + 2H2O concentrated

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Copper has a fairly high resistance to corrosion. However, in a humid atmosphere containing carbon dioxide, copper is covered with a greenish coating of basic copper carbonate: 2Сu + O2 + СO2 + Н2O = СU(ОН)2 СuСО3 - the most characteristic and stable. Copper (II) forms stable CuO oxide and Cu(OH)2 hydroxide. This hydroxide is amphoteric, readily soluble in acids Сu(OH)2 + 2НCl = СuСl2 + 2Н2О and in concentrated alkalis. Salts of copper (II) are widely used in the national economy. Especially important is copper sulphate - hydrated copper (II) sulfate CuSO4 5H2.

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Copper and Health The human body needs copper for the formation of various proteins and enzymes. Copper is needed: For the synthesis of hemoglobin For the formation of bones For the functioning of the circulatory system For the functioning of the central nervous system To obtain energy from cells Recent studies have shown that the assumption that a diet with insufficient copper content increases the risk of cardiovascular diseases is very close to the truth. Copper deficiency in the body can lead to such serious consequences as bone malformation, anemia and brain failure. Further consequences are: Blockage of cellular respiration Stopping the formation of uric acid Incorrect formation of neurotransmitters Stopping the formation of pigments (white hair) Violation of the redox balance

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A person, along with food, must receive a certain amount of copper in order to sufficiently saturate the body with this element. The daily requirement of an adult for copper is 2-3 mg. Many foods and drinks contain this important element in various quantities. single consumption drinking water with copper ions is not enough. Foods high in copper include: Chocolate White and green beans Fish Hazelnuts and southern nuts Conversely, the following foods contain only low amounts of copper: Cheese Milk White bread Beef and lamb This table lists foods and their copper content

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Allocated technical metal containing 97 - 98% copper. One of the most important industries for the use of copper is the electrical industry. Electrical wires are made from copper. For this purpose, the metal must be very pure: impurities sharply reduce the electrical conductivity. The presence of 0.02% aluminum in copper will reduce its electrical conductivity by almost 10%. The resistance of a metal increases even more sharply in the presence of non-metallic impurities. To obtain pure copper, which can be used in electrical engineering, it is electrorefined. This method is based on the electrolysis of an aqueous solution of copper salt with a soluble copper anode. Technical or blister copper, which serves as one of the electrodes, is immersed in a bath filled with an aqueous solution of copper sulfate. Another electrode is immersed in the bath. A direct current source is connected to the electrodes in such a way that technical copper becomes the anode (the positive pole of the current source), and the other electrode becomes the cathode.

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A very important area of application of copper is the production of copper alloys. With many metals, copper forms the so-called solid solutions, which are similar to ordinary solutions in that in them the atoms of one component (metal) are evenly distributed among the atoms of another (Fig. 34). Most copper alloys are solid solutions. An alloy of copper known since ancient times - bronze - contains 4-30% tin (usually 8-10%). It is interesting that bronze in its hardness surpasses separately taken pure copper and tin. Bronze is more fusible than copper. Bronze products of the masters of Ancient Egypt, Greece, and China have survived to this day. In the Middle Ages, tools and many other products were cast from bronze. The famous Tsar Cannon (Fig. 35) and the Tsar Bell in the Moscow Kremlin are also cast from an alloy of copper and tin.

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The healing properties of copper have been known for a very long time. The ancients believed that the healing effect of copper is associated with its analgesic, antipyretic, antibacterial and anti-inflammatory properties. Even Avicenna and Galen described copper as a medicine, and Aristotle, pointing to the general strengthening effect of copper on the body, preferred to fall asleep with a copper ball in his hand. Queen Cleopatra wore the thinnest copper bracelets, preferring them to gold and silver, knowing medicine and alchemy well. In copper armor, ancient warriors got less tired, and their wounds festered less and healed faster. The ability of copper to positively influence “male power” was noticed and widely used in the ancient world. ethnoscience

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Nowadays, the use of copper products is widespread. In Central Asia, they wear copper products and practically do not suffer from rheumatism. In Egypt and Syria, even children wear copper items. In France, hearing disorders are treated with copper. In the US, copper bracelets are worn as a remedy for arthritis. In Chinese medicine, copper disks are applied to active points. And in Nepal, copper is considered a sacred metal. Medetherapy (copper treatment) is one of the types of traditional medicine. In childhood, applying a copper penny on a bump on the advice of my grandmother, we reduced pain and inflammation, although in a 5-kopeck coin issued in Soviet time, the copper content was low. In medical therapy, products with a copper content of at least 99.9% are used. The simplest, most effective, aesthetically beautiful and practical tool in medical therapy is a copper bracelet, approved and recommended by the Ministry of Health of the Russian Federation.

Copper is a heavy pink-red metal, soft and malleable, its melting point is 1083 ° C, it is an excellent conductor of electric current and heat, the electrical conductivity of copper is 1.7 times higher than aluminum, and 6 times higher than iron. In everyday life, we have to deal with copper and its alloys all the time: we turn on a computer or a table lamp, current flows through copper wires, we use metal money, which, both yellow and white, are made of copper alloys. Some houses are decorated with bronze items, utensils are made of copper. Meanwhile, copper is far from the most common element in nature: the copper content in the earth's crust is 0.01%, which allows it to occupy only 23rd place among all elements.

Copper is the first metal that was first used by man in antiquity, several millennia BC. The first copper tools were made from native copper, which is quite common. The largest copper nugget was found in the United States, it had a mass of 420 tons. But in view of the fact that copper is a soft metal, copper in ancient times could not displace stone tools. Only when man learned to melt copper and invented bronze (an alloy of copper and tin) did metal replace stone. The widespread use of copper began in the 4th millennium BC. e. Copper is an inactive metal; in the electrochemical series of voltages, it is to the right of hydrogen. It does not interact with water, alkali solutions, hydrochloric and dilute sulfuric acid. However, in strong oxidizing acids (for example, nitric and concentrated sulfuric), copper dissolves: Cu + 4HMO3 - Cu (NO3) 2 + 2NO + 2H2O concentrated

Copper has a fairly high resistance to corrosion. However, in a humid atmosphere containing carbon dioxide, copper is covered with a greenish coating of basic copper carbonate: 2Сu + O2 + СO2 + Н2O = СU(ОН)2 СuСО3 the most characteristic and stable. Copper (II) forms stable CuO oxide and Cu(OH)2 hydroxide. This hydroxide is amphoteric, readily soluble in acids Сu(OH)2 + 2НCl = СuСl2 + 2Н2О and in concentrated alkalis. Salts of copper (II) are widely used in the national economy. Of particular importance is copper sulphate, hydrated copper (II) sulfate CuSO4 5H2.

A person, along with food, must receive a certain amount of copper in order to sufficiently saturate the body with this element. The daily requirement of an adult for copper is 2-3 mg. Many foods and drinks contain this important element in varying amounts. One consumption of drinking water with copper ions is not enough. Foods high in copper include: Chocolate White and green beans Fish Hazelnuts and southern nuts Conversely, the following foods contain only low amounts of copper: Cheese Milk White bread Beef and lamb This table lists foods and their copper content

The technical metal containing 97 98% of copper is allocated. One of the most important industries for the use of copper is the electrical industry. Electrical wires are made from copper. For this purpose, the metal must be very pure: impurities sharply reduce the electrical conductivity. The presence of 0.02% aluminum in copper will reduce its electrical conductivity by almost 10%. The resistance of a metal increases even more sharply in the presence of non-metallic impurities. To obtain pure copper, which can be used in electrical engineering, it is electrorefined. This method is based on the electrolysis of an aqueous solution of copper salt with a soluble copper anode. Technical or blister copper, which serves as one of the electrodes, is immersed in a bath filled with an aqueous solution of copper sulfate. Another electrode is immersed in the bath. A direct current source is connected to the electrodes in such a way that technical copper becomes the anode (the positive pole of the current source), and the other electrode is the cathode.

A very important area of application of copper is the production of copper alloys. With many metals, copper forms so-called solid solutions, which are similar to ordinary solutions in that in them the atoms of one component (metal) are evenly distributed among the atoms of another (Fig. 34). Most copper alloys are solid solutions. An alloy of copper known since ancient times, bronze contains 430% tin (usually 810%). It is interesting that bronze in its hardness surpasses separately taken pure copper and tin. Bronze is more fusible than copper. Bronze products of the masters of Ancient Egypt, Greece, and China have survived to this day. In the Middle Ages, tools and many other products were cast from bronze. The famous Tsar Cannon (Fig. 35) and the Tsar Bell in the Moscow Kremlin are also cast from an alloy of copper and tin.

Nowadays, the use of copper products is widespread. In Central Asia, they wear copper products and practically do not suffer from rheumatism. In Egypt and Syria, even children wear copper items. In France, hearing disorders are treated with copper. In the US, copper bracelets are worn as a remedy for arthritis. In Chinese medicine, copper disks are applied to active points. And in Nepal, copper is considered a sacred metal. Medetherapy (copper treatment) is one of the types of traditional medicine. In childhood, applying a copper penny on a bump on the advice of my grandmother, we reduced pain and inflammation, although the copper content was low in a 5-kopeck coin issued in the Soviet era. In medical therapy, products with a copper content of at least 99.9% are used. The simplest, most effective, aesthetically beautiful and practical tool in medical therapy is a copper bracelet, approved and recommended by the Ministry of Health of the Russian Federation.