Malleability of copper. Copper characteristic

The ductility is the susceptibility of metals and alloys to forging and other types of pressure treatment. This can be drawing, stamping, rolling or pressing. Copper ductility characterized not only by deformation resistance, but also by ductility. What is plasticity? This is the ability of a metal to change its contours under pressure without destruction. Malleable metals are brass, steel, duralumin and some other copper, magnesium, nickel, and aluminum alloys. They have a high level of ductility combined with low resistance to deformation.

Copper

I wonder what the characteristic of copper looks like? It is known that this is an element of group 11 of the period of the system of chemical elements of D. I. Mendeleev. Its atom has 29 numbers and is denoted by the symbol Cu. In fact, it is a transition metal of pinkish-golden color. By the way, it is pink if there is no oxide film. For a long time this element is 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 be obtained from ore and has a low melting point. 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 copper objects, slag, are evidence of its smelting from ores. They were discovered during excavations of the village of Chatal-Hyuk. It is known that in the copper age copper things became widespread. In world history, it follows stone.

S. A. Semenov and his colleagues conducted experimental studies in which he found out that copper tools in comparison with stone tools win in many respects. They have a higher speed of planing, drilling, cutting and sawing wood. And bone treatment with a copper knife lasts as much as a stone knife. But copper is considered a soft metal.

Very often in antiquity, instead of copper, its alloy with tin was used - bronze. It was necessary for the manufacture of weapons and other things. So, the bronze age has replaced the copper age. Bronze was first received in the Middle East for 3000 years BC. e.: people liked the strength and excellent malleability of copper. From the resulting bronze came out magnificent tools of labor and hunting, dishes, jewelry. All these items are found in archaeological sites. Further, the Bronze Age was replaced by the Iron.

How to get copper in ancient times? Initially, it was extracted not from sulfide, but from malachite ore. Indeed, in this case it was not necessary to engage in preliminary firing. For this, a mixture of coal and ore was placed in an earthenware pot. The vessel was installed in a shallow pit and the mixture was set on fire. Then carbon monoxide began to be released, which contributed to the recovery of malachite to free copper.

It is known that in Cyprus already in the third millennium BC, copper mines were built, on which it was smelted.

On the lands of Russia and neighboring states, copper mines arose two millennia BC. e. Their ruins are found in the Urals, Ukraine, Transcaucasia, Altai, and distant Siberia.

Industrial copper smelting 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 spent on making bells. In 1586, the Tsar Cannon was cast from bronze, in 1735 the Tsar Bell, and in 1782 the Bronze Horseman was created. In 752, the craftsmen made a magnificent statue of the Big Buddha in the Todai-ji Temple. In general, the list of foundry works is endless.

In the eighteenth century, man discovered electricity. It was then that huge volumes of copper began to go to the manufacture of wires and similar products. In the twentieth century, wires learned to make aluminum, but copper was still of great importance in electrical engineering.

origin of name

Did you know that Cuprum is the Latin name for copper, derived from the name of the island of Cyprus? By the way, at Strabo copper is called chalcos - the city of Chalkis on Euboea is guilty of the origin of such a name. Most of the ancient Greek names for copper and bronze objects came from this very word. They are widely used in blacksmithing, and among blacksmiths 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 oldest literary monuments of Russia. V. I. Abaev assumed that this word came from the name of the country of Midia. 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 weight). In river and sea water it is much less: 10 ^-7 % and 3 x 10 ^-7 % (by weight), respectively.

Copper compounds are very often found in nature. In industry, chalcopyrite CuFeS ₂ , called copper pyrite, boronite Cu ₅ FeS ₄ , chalcosine Cu ₂ S is used. At the same time, people find other copper minerals: cuprite Cu ₂ O, azurite Cu ₃ (CO ₃ ) ₂ (OH) ₂ , malachite Cu ₂ CO ₃ (OH) ₂ and covellin 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 you can find copper deposits - shale and copper sandstones. The most famous deposits are in the Trans-Baikal Territory Udokan, Zhezkazgan in Kazakhstan, Mansfeld in Germany and the melliferous belt of Central Africa. Other richest deposits of copper are located in Chile (Coliausi and Escondida) and the USA (Morensi).

Most of the copper ore is mined open pit. It contains from 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 gray or silver of other metals. This color shade indicates the presence of electronic transitions between the fourth half-empty and the third atomic orbitals filled with the third. There is a certain energy difference between them, corresponding to the wavelength of the orange color. The same system is responsible for the specific color of gold.

What is more surprising characteristic of copper? This metal forms a face-centered cubic lattice, space group Fm3m, a = 0.36150 nm, Z = 4.

And copper is also famous for its high electrical and thermal conductivity. By conducting current, it is among metals in second place. By the way, copper has a giant temperature coefficient of resistance and in a wide temperature range is almost independent of its performance. Copper is called a diamagnet.

Copper alloys are diverse. People have learned to combine brass with zinc, nickel and nickel silver, and lead with babbits, and bronze with tin and other metals.

Copper isotopes

Copper consists of two stable isotopes - ⁶³ Cu and ⁶⁵ Cu, which have a prevalence 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 ⁶⁷ Cu with a half-life of 62 hours.

How to get copper?

Making copper is a very interesting process. This metal is obtained from minerals and copper ores. The basic methods for producing copper are hydrometallurgy, pyrometallurgy and electrolysis.

Consider the pyrometallurgical method. In this way, copper is obtained from sulfide ores, for example, chalcopyrite CuFeS ₂ . Chalcopyrite feed contains 0.5-2.0% Cu. Initially, the source ore undergoes flotation concentration. Then, its oxidative firing is performed at a temperature of 1400 degrees. Next, the calcined concentrate goes to matte smelting. Silica is added to the melt to bind iron oxide.

The resulting silicate floats in the form of slag, and it is separated. The matte remains at the bottom - an alloy of sulfides CU ₂ S and FeS. Then it is melted according to the method of Henry Bessemer. To do this, pour molten matte into the converter. Then the container is purged with oxygen. And the iron sulfide that remains is oxidized to oxide and, using silica, is removed from the process in the form of silicate. Copper sulfide is oxidized to copper oxide incompletely, but then reduced to metallic copper.

The resulting blister copper contains 90.95% of the metal. Then it is subjected to electrolytic cleaning. Interestingly, an acidified solution of copper sulfate is used as the electrolyte .

Electrolytic copper is formed at the cathode, which has a high frequency of about 99.99%. Items made of copper obtained are made very different: wires, electrical equipment, alloys.

The hydrometallurgical method looks somewhat different. Here, copper minerals are dissolved in diluted sulfuric acid or in ammonia solution. Copper is replaced by metallic iron from the prepared liquids.

Chemical properties of copper

In compounds, copper shows two oxidation states: +1 and +2. The first of them tends to disproportionate and is stable only in insoluble compounds or complexes. By the way, copper compounds are colorless.

The oxidation state +2 is more stable. It is she who gives the salt a blue and blue-green color. Under unusual conditions, compounds with oxidation state of +3 and even +5 can be prepared. The latter is usually found in the salts of cupraborane anion 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. It is oxidized by concentrated nitric and sulfuric acids, halogens, oxygen, aqua regia, non-metal oxides, and chalcogenes. When heated, it reacts with hydrogen halides.

If the air is humid, copper is oxidized to form basic copper (II) carbonate. It perfectly reacts 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 introduce it into the flame of a Bunsen burner. If copper is present in the solution, the flame will turn green-blue. You need to know that:

• Typically, the amount of copper in slightly acidic solutions is measured using hydrogen sulfide: it is mixed with a substance. Typically, copper sulphide precipitates.
• In those solutions where there are no interfering ions, copper is determined by complexometric, ionometric, or potentiometric measurements.
• Small amounts of copper in solutions are measured by spectral and kinetic methods.

Copper application

Agree study 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 0.02% aluminum is present in copper, its electrical conductivity will decrease by 10%.

The second useful quality of copper is its excellent thermal conductivity. Due to this property, it is used in various heat exchangers, heat pipes, heat sink devices and computer coolers.

And where is the hardness of copper used? It is known that seamless copper tubes of circular cross section have remarkable mechanical strength. They withstand mechanical processing and are used to move gases and liquids. Usually they can be found in internal gas supply, water, heating systems. They are widely used in refrigeration units and air conditioning systems.

The excellent hardness of copper is known to many countries. So, in France, Great Britain 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 standardized by the GOST R 52318-2005 standard, and the federal code of rules SP 40-108-2004 regulates their application. Pipes made of copper and its alloys are actively used in energy and shipbuilding to move steam and liquids.

Do you know that copper alloys are used in various fields of technology? Of these, the most famous are bronze and brass. Both alloys include a colossal family of materials, which, in addition to zinc and tin, can include bismuth, nickel and other metals. For example, cannon bronze, used until the nineteenth century for the manufacture of artillery pieces, consisted of copper, tin and zinc. Its recipe changed depending on the place and time of manufacture of the gun.

Everyone knows the excellent manufacturability and high ductility of copper. Thanks to these properties, an incredible amount of brass is spent on the production of cartridges for weapons and artillery ammunition. It is noteworthy that auto parts are made from alloys of copper with silicon, zinc, tin, aluminum and other materials. Copper alloys are highly durable 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. It should be noted that this rule does not apply to beryllium bronze and some aluminum bronzes.

Copper alloys have an elastic modulus lower than that of steel. Their main advantage can be called a small coefficient of friction, which is combined for most alloys with high ductility, excellent electrical conductivity and excellent corrosion resistance in an aggressive environment. As a rule, these are aluminum bronzes and copper-nickel alloys. By the way, they found their application in slip pairs.

Almost all copper alloys have the same value of the 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. Copper ductility used in single-phase alloys, and strength - in two-phase alloys. Cupronickel (copper-nickel alloy) is used for minting small coins. Copper-nickel alloys, including the "Admiralty", are used in shipbuilding. They make tubes for condensers that clean the turbine exhaust steam. It is noteworthy that the turbines are cooled by sea water. Copper-nickel alloys have amazing corrosion resistance, so they try to use them in areas associated with the aggressive influence of sea water.

In fact, copper is the most important component of brazing alloys - alloys having a melting point of 590 to 880 degrees Celsius. They are inherent in the remarkable adhesion to most metals, so they are used for durable connection of various metal parts. It can be pipe fittings or liquid-propellant jet engines made of dissimilar metals.

And now we list alloys in which the malleability of copper is of great importance. Duralumin or duralumin is an alloy of aluminum and copper. Here, copper is 4.4%. Copper alloys with gold are often used in jewelry. They are necessary to increase the strength of products. Indeed, pure gold is a very soft metal, which cannot be resistant to mechanical stress. Pure gold items 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 for the production of batteries and copper oxide cells.

Other areas of application

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 to be used only when the copper content in them does not exceed 64%.

People have learned to use the malleability of copper in architecture as well. Facades and roofs made of the finest sheet of copper have been trouble-free for 150 years. This phenomenon is simply explained: auto-damping of the corrosion process occurs in copper sheets. 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 near future, people plan to use copper as bactericidal surfaces in clinics to prevent bacteria from moving indoors. All surfaces to which the human hand touches — doors, handles, railings, water fittings, countertops, beds — will be made by specialists only from this amazing metal.

Copper marking

What brands of copper does a person use to produce the products he needs? There are many of them: M00, M0, M1, M2, M3. In general, grades of copper are identified by the purity of its content.

For example, copper of brands M1p, M2p and M3p contains 0.04% phosphorus and 0.01% oxygen, and brands M1, M2 and M3 contain 0.05-0.08% oxygen. In the M0b brand, oxygen is absent, and in the MO its percentage is 0.02%.

So, we will consider copper in more detail. The table below will provide more accurate information:

27 brands of copper

There are twenty seven grades of copper in total. Where is the amount of copper materials used by man? Consider this nuance in more detail:

• Cu-DPH is used for the manufacture of fittings necessary for connecting pipes.
• AMP is needed to create hot-rolled and cold-rolled anodes.
• AMPs are 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 necessary for the manufacture of electrical products.
• M00b is used to create current conductors, high-frequency alloys and apparatuses of the electric vacuum industry.
• M00k is the feedstock for creating deformed and cast billets.
• M0b is used to create alloys with a high frequency.
• M0k is used for the production of cast and deformed billets.
• M1 is needed for the manufacture of wire and cryogenic technology products.
• M16 is used for the manufacture of devices in the electric vacuum industry.
• M1E is needed to create cold rolled foil and tape.
• M1k is needed to create convenience foods.
• M1op is used for the manufacture of wire and other electrical products.
• M1p is used for the manufacture of electrodes used for welding cast iron and copper.
• 1 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 for the manufacture of high-grade alloys and semi-finished products based on copper.
• M2k is used for the production of convenience foods.
• M2p is necessary for the manufacture of rods.
• M3 is needed for the manufacture of rolled products, alloys.
• M3p is used to create rolled products and alloys.
• MB-1 is needed to create beryllium-containing bronzes.
• MCP1 is used for the manufacture of electrical structures.