Malleability refers to the susceptibility of metals and alloys to forging and other types of pressure treatment. It can be drawing, stamping, rolling or pressing. The ductility of copper is characterized not only by resistance to deformation, but also by ductility. What is plasticity? This is the ability of metal to change its contours under pressure without destruction. Malleable metals are brass, steel, duralumin and some other copper, magnesium, nickel, aluminum alloys. It is they who have a high level of plasticity combined with a low resistance to deformation.
Copper
I wonder what the characteristic of copper looks like? It is known that this is an element of the 11th group of the 4th period of the system of chemical elements of D. I. Mendeleev. Its atom has number 29 and is denoted by the symbol Cu. In fact, it is a transitional ductile metal of a pinkish-gold color. By the way, it has a pink color if the oxide film is absent. For a long time, this element has been used by people.
History
One of the first metals that people began to actively use in their households is copper. Indeed, it is too accessible to obtain from ore and has a smallmelting temperature. For a long time, the human race has known the seven metals, which also includes copper. In nature, this element is much more common than silver, gold or iron. Ancient objects made of copper, slag, are evidence of its smelting from ores. They were discovered during the excavations of the village of Chatal-Khuyuk. It is known that in the Copper Age, copper things became widespread. In world history, he follows the stone one.
S. A. Semyonov and his colleagues conducted experimental studies in which he found out that copper tools are superior to stone tools in many ways. They have a higher speed of planing, drilling, cutting and sawing wood. And processing a bone with a copper knife lasts as long as with a stone one. But copper is considered a soft metal.
Very often in ancient times, instead of copper, they used its alloy with tin - bronze. It was necessary for the manufacture of weapons and other things. So, the bronze age came to replace the copper age. Bronze was first obtained in the Middle East in 3000 BC. AD: People liked the strength and excellent malleability of copper. Magnificent tools of labor and hunting, utensils, and decorations came out of the resulting bronze. All these items are found in archaeological excavations. Then the Bronze Age was replaced by the Iron Age.
How could copper be obtained in ancient times? Initially, it was mined not from sulfide, but from malachite ore. Indeed, in this case, there was no need to engage in preliminary firing. To do this, a mixture of coal and ore was placed in an earthenware vessel. The vessel was placed ina shallow hole and the mixture was set on fire. Then carbon monoxide began to be released, which contributed to the reduction of malachite to free copper.
It is known that copper mines were built in Cyprus already in the third millennium BC, where copper was smelted.
On the lands of Russia and neighboring states, copper mines arose two millennia BC. e. Their ruins are found in the Urals, and in Ukraine, and in the Transcaucasus, and in Altai, and in distant Siberia.
Industrial smelting of copper was mastered in the thirteenth century. And in the fifteenth in Moscow, the Cannon Yard was created. It was there that guns of various calibers were cast from bronze. An incredible amount of copper was used to make bells. In 1586, the Tsar Cannon was cast from bronze, in 1735 - the Tsar Bell, in 1782 the Bronze Horseman was created. In 752, craftsmen made a magnificent statue of the Big Buddha at Todai-ji Temple. In general, the list of works of foundry art is endless.
In the eighteenth century man discovered electricity. It was then that huge volumes of copper began to go into the manufacture of wires and similar products. In the twentieth century, wires were made from aluminum, but copper was still of great importance in electrical engineering.
Origin of the name
Do you know that Cuprum is the Latin name for copper, derived from the name of the island of Cyprus? By the way, Strabo calls copper chalkos - the city of Chalkis on Euboea is guilty of the origin of such a name. Most of the ancient Greek names for copper andbronze objects originated precisely from this word. They have found wide application in blacksmithing, and among blacksmith products and castings. Sometimes copper is called Aes, which means ore or mine.
The Slavic word "copper" does not have a pronounced etymology. Perhaps it is old. But it is very often found in the most ancient literary monuments of Russia. V. I. Abaev assumed that this word came from the name of the country Midia. The alchemists nicknamed copper "Venus". In more ancient times, it was called "Mars".
Where is copper found in nature?
The Earth's crust contains (4, 7-5, 5) x 10-3% copper (by mass). In river and sea water, it is much less: 10-7% and 3 x 10-7% (by mass) respectively.
Copper compounds are often found in nature. The industry uses chalcopyrite CuFeS2, called copper pyrite, bornite Cu5FeS4, chalcocite Cu 2S. At the same time, people find other copper minerals: cuprite Cu2O, azurite Cu3(CO3) 2(OH)2, Malachite Cu2CO3 (OH)2 and covelline CuS. Very often, the mass of individual accumulations of copper reaches 400 tons. Copper sulfides are formed mainly in hydrothermal medium-temperature veins. Often, in sedimentary rocks, copper deposits can be found - shales and cuprous sandstones. The most famous deposits are in the Trans-Baikal Territory Udokan, Zhezkazgan in Kazakhstan, Mansfeld in Germany and the honey belt of Central Africa. Other richest copper deposits are locatedin Chile (Colhausi and Escondida) and USA (Morenci).
Most of the copper ore is mined open-pit. It contains 0.3 to 1.0% copper.
Physical properties
Many readers are interested in the description of copper. It is a ductile pinkish-gold metal. In air, its surface is instantly covered with an oxide film, which gives it a peculiar intense red-yellow hue. Interestingly, thin films of copper have a bluish-green color.
Osmium, cesium, copper and gold have the same color, different from the gray or silver of other metals. This color shade indicates the presence of electronic transitions between the fourth half-empty and the filled third atomic orbitals. Between them there is a certain energy difference corresponding to the wavelength of orange. The same system is responsible for the specific color of gold.
What else is amazing about copper? This metal forms a face-centered cubic lattice, space group Fm3m, a=0.36150 nm, Z=4.
Copper is also famous for its high electrical and thermal conductivity. In terms of current conduction, it is among the metals in second place. By the way, copper has a giant temperature coefficient of resistance and is almost independent of its performance over a wide temperature range. Copper is called a diamagnet.
Copper alloys are diverse. People have learned to combine brass with zinc, and nickel with cupronickel, and lead with babbits,and bronze with tin and other metals.
Isotopes of copper
Copper is made up of two stable isotopes, 63Cu and 65Cu, which have abundances of 69.1 and 30.9 percent atomic respectively. In general, there are more than two dozen isotopes that do not have stability. The longest lived isotope is 67Cu with a half-life of 62 hours.
How is copper obtained?
Making copper is a very interesting process. This metal is obtained from minerals and copper ores. The basic methods for obtaining copper are hydrometallurgy, pyrometallurgy and electrolysis.
Let's consider the pyrometallurgical method. In this way, copper is obtained from sulfide ores, for example, chalcopyrite CuFeS2. Chalcopyrite raw material contains 0.5-2.0% Cu. First, the original ore is subjected to flotation enrichment. Then it is oxidized roasted at a temperature of 1400 degrees. Next, the calcined concentrate is smelted for matte. Silica is added to the melt to bind iron oxide.
The resulting silicate floats up as slag and is separated. Matte remains at the bottom - an alloy of sulfides CU2S and FeS. Then it is melted according to the method of Henry Bessemer. To do this, molten matte is poured into the converter. The vessel is then purged with oxygen. And the iron sulfide that remains is oxidized to oxide and, with the help of silica, is removed from the process in the form of silicate. Copper sulfide is oxidized to copper oxide incompletely, but then it is reduced to metallic copper.
Bthe resulting blister copper contains 90.95% of the metal. Then it is subjected to electrolytic purification. Interestingly, an acidified solution of copper sulphate is used as an electrolyte.
Electrolytic copper is formed on the cathode, which has a high frequency of about 99.99%. A variety of items are made from copper obtained: wires, electrical equipment, alloys.
The hydrometallurgical method looks a bit different. Here, copper minerals are dissolved in dilute sulfuric acid or in ammonia solution. From the prepared liquids, copper is displaced by metallic iron.
Chemical properties of copper
In compounds, copper shows two oxidation states: +1 and +2. The first of them tends to disproportionation and is stable only in insoluble compounds or complexes. By the way, copper compounds are colorless.
Oxidation state +2 is more stable. It is she who gives the s alt blue and blue-green color. Under unusual conditions, compounds with an oxidation state of +3 and even +5 can be prepared. The latter is usually found in cupbororane anion s alts obtained in 1994.
Pure copper does not change in air. It is a weak reducing agent that does not react with dilute hydrochloric acid and water. Oxidized by concentrated nitric and sulfuric acids, halogens, oxygen, aqua regia, non-metal oxides, chalcogens. When heated, it reacts with hydrogen halides.
If the air is humid, copper oxidizes to form basic copper(II) carbonate. It reacts great with cold and hot saturated sulfuric acid, hot anhydrous sulfuric acid.
Copper reacts with dilute hydrochloric acid in the presence of oxygen.
Analytical chemistry of copper
Everyone knows what chemistry is. Copper in solution is easy to detect. To do this, it is necessary to moisten the platinum wire with the test solution, and then bring it into the flame of the Bunsen burner. If copper is present in the solution, the flame will be blue-green. You need to know that:
- Usually, the amount of copper in slightly acidic solutions is measured using hydrogen sulfide: it is mixed with the substance. As a rule, copper sulfide precipitates in this case.
- In those solutions where there are no interfering ions, copper is determined complexometrically, ionometrically or potentiometrically.
- Small amounts of copper in solutions are measured by spectral and kinetic methods.
Copper use
Agree, the study of copper is a very entertaining thing. So, this metal has a low resistivity. Due to this quality, copper is used in electrical engineering for the production of power and other cables, wires and other conductors. Copper wires are used in the windings of power transformers and electric drives. To create the above products, the metal is selected very pure, since impurities instantly reduce electrical conductivity. And if there is 0.02% aluminum in copper, its electrical conductivity will decrease by 10%.
The second useful quality of copper isexcellent thermal conductivity. Due to this property, it is used in various heat exchangers, heat pipes, heat sinks and computer coolers.
And where is the hardness of copper used? It is known that seamless round copper tubes have remarkable mechanical strength. They perfectly withstand mechanical processing and are used to move gases and liquids. Usually they can be found in internal gas supply systems, water supply, heating. They are widely used in refrigeration units and air conditioning systems.
The excellent hardness of copper is known to many countries. So, in France, the UK and Australia, copper pipes are used for gas supply to buildings, in Sweden - for heating, in the USA, Great Britain and Hong Kong - this is the main material for water supply.
In Russia, the production of water and gas copper pipes is regulated by the GOST R 52318-2005 standard, and the federal Code of Rules SP 40-108-2004 regulates their use. Pipes made of copper and its alloys are actively used in the power industry and shipbuilding to move steam and liquids.
Do you know that copper alloys are used in various fields of technology? Of these, bronze and brass are considered the most famous. Both alloys comprise a colossal family of materials that, in addition to zinc and tin, may include bismuth, nickel, and other metals. For example, gunmetal, used until the nineteenth century to make artillery pieces, consisted of copper, tin, and zinc. Its recipe changed depending on the place andtool manufacturing time.
Everyone knows the excellent manufacturability and high ductility of copper. Due to these properties, an incredible amount of brass goes into the production of shells for weapons and artillery ammunition. It is noteworthy that auto parts are made from copper alloys with silicon, zinc, tin, aluminum and other materials. Copper alloys are characterized by high strength and retain their mechanical properties during heat treatment. Their resistance to wear is determined only by the chemical composition and its effect on the structure. Please note that this rule does not apply to beryllium bronze and some aluminum bronzes.
Copper alloys have a lower modulus of elasticity than steel. Their main advantage can be called a small coefficient of friction, combined for most alloys with high ductility, excellent electrical conductivity and excellent resistance to corrosion in an aggressive environment. As a rule, these are aluminum bronzes and copper-nickel alloys. By the way, they have found their application in slip pairs.
Practically all copper alloys have the same coefficient of friction. At the same time, wear resistance and mechanical properties, behavior in an aggressive environment directly depend on the composition of the alloys. The ductility of copper is used in single-phase alloys, and the strength is used in two-phase alloys. Cupronickel (copper-nickel alloy) is used for minting change coins. Copper-nickel alloys, including "Admir alty", are used in shipbuilding. They are used to make tubes for condensers that clean turbine exhaust steam. It is noteworthy that the turbines are cooled by outboard water. Copper-nickel alloys have amazing corrosion resistance, so they are sought after in areas subject to the aggressive effects of sea water.
In fact, copper is the most important component of hard solders - alloys with a melting point of 590 to 880 degrees Celsius. It is they who have excellent adhesion to most metals, due to which they are used to firmly connect various metal parts. These can be pipe fittings or liquid-propellant jet engines made from dissimilar metals.
And now we list the alloys in which the malleability of copper is of great importance. Dural or duralumin is an alloy of aluminum and copper. Here copper is 4.4%. Alloys of copper and gold are often used in jewelry. They are necessary to increase the strength of products. After all, pure gold is a very soft metal that cannot be resistant to mechanical stress. Items made of pure gold quickly deform and wear out.
Interestingly, copper oxides are used to create yttrium-barium-copper oxide. It serves as the basis for the manufacture of high-temperature superconductors. Copper is also used to make batteries and copper oxide cells.
Other applications
Do you know that copper is often used as a catalyst for the polymerization of acetylene? Due to this property, copper pipelines used to transport acetylene are allowed touse only when the copper content in them does not exceed 64%.
People have learned to use the malleability of copper in architecture. Facades and roofs made of the thinnest sheet copper serve trouble-free for 150 years. This phenomenon is explained simply: in copper sheets, the corrosion process auto-extinguishes. In Russia, copper sheet is used for facades and roofs in accordance with the norms of the Federal Code of Rules SP 31-116-2006.
In the not too distant future, people are planning to use copper as germicidal surfaces in clinics to keep bacteria from moving around indoors. All surfaces touched by the human hand - doors, handles, railings, water fittings, countertops, beds - will be made by specialists only from this amazing metal.
Copper Marking
What grades of copper does a person use to produce the products he needs? There are many of them: M00, M0, M1, M2, M3. In general, copper grades are identified by the purity of their content.
For example, copper grades M1r, M2r and M3r contains 0.04% phosphorus and 0.01% oxygen, and grades M1, M2 and M3 - 0.05-0.08% oxygen. There is no oxygen in the M0b grade, and in MO its percentage is 0.02%.
So let's take a closer look at copper. The table below will provide more accurate information:
| Copper Grade | M00 | M0 | M0b | M1 | M1p | M2 | M2r | M3 | M3r | M4 |
|
Percentage contents copper |
99, 99 | 99, 95 | 99, 97 | 99, 90 | 99, 70 | 99, 70 | 99, 50 | 99, 50 | 99, 50 | 99, 00 |
27 copper grades
There are twenty-seven grades of copper in total. Where does a person use such an amount of copper materials? Consider this nuance in more detail:
- Cu-DPH material is used to make fittings needed to connect pipes.
- AMF is needed to create hot-rolled and cold-rolled anodes.
- AMPU is used for the production of cold-rolled and hot-rolled anodes.
- M0 is needed to create current conductors and high-frequency alloys.
- Material M00 is used for the manufacture of high-frequency alloys and current conductors.
- M001 is used for the manufacture of wire, tires and other electrical products.
- M001b is required for the manufacture of electrical products.
- M00b is used to create current conductors, high-frequency alloys and devices for the electrovacuum industry.
- M00k - raw material for creating deformed and cast blanks.
- M0b is used to create high frequency alloys.
- M0k is used for the production of cast and deformed blanks.
- M1 needed for manufacturingwire and products of cryogenic technology.
- M16 is used for the production of devices for the vacuum industry.
- M1E is needed to create cold rolled foil and strip.
- M1k is needed to create semi-finished products.
- M1op is used for the manufacture of wire and other electrical products.
- M1p is used to make electrodes used for welding cast iron and copper.
- M1pE is needed for the production of cold rolled strip and foil.
- M1u is used to create cold-rolled and hot-rolled anodes.
- M1f is needed to create tape, foil, hot-rolled and cold-rolled sheets.
- M2 is used to make high-quality copper-based alloys and semi-finished products.
- M2k is used for the production of semi-finished products.
- M2p is needed to make bars.
- M3 is needed for the manufacture of rolled products, alloys.
- M3r is used to create rolled products and alloys.
- MB-1 is needed to create beryllium-containing bronzes.
- MSr1 is used for the manufacture of electrical structures.
