How is brass obtained? Brass - what is included? How can you tell brass alloy from bronze

A metal alloy called brass refers to multi-component or double materials, where copper is the main component, and zinc is the alloying substance. Lead, tin, aluminum, nickel, manganese, as well as iron and other metals can be added to this composition. Brass is a substance that resembles gold, but its value is much lower than the precious metal. The color and its properties directly depend on the percentage of incoming components. However, according to the metallurgical classification, it does not belong to bronze.

Composition, structure

The basis of the copper alloy is zinc, which has been used for three centuries. Depending on the chemical composition, it happens:

• two-component;
• multicomponent.

Two-component

This composition contains zinc and a copper component in various volumes. In accordance with GOST, it is designated by the letter "L" and digital designations. The numeric value indicates the percentage of copper. For grade L63, the copper component will have 63%, and zinc - 37%.

Multicomponent

This is brass, the alloy composition of which contains alloying substances. These include aluminum, lead, and other metals. Such a grade is designated depending on the incoming components, while the share of the zinc component is obtained by subtracting from 100% of the parts of other components. The composition of the brass alloy marked LS60-5 means, when deciphered, that copper is 60%, lead is 5%, and zinc is 35%. The share of additional impurities usually does not exceed 10%. The ratio of incoming components may vary slightly. In this case, the zinc part usually does not exceed 35%. For a complete understanding of the composition, it is necessary to disassemble what is technical brass? These are special alloys, where the share of zinc reaches 50%.

Red brass contains part of zinc in the range from 5 to 20%, and in yellow its share is more than 20%.

Application area

Brass alloy is one of the most common among a wide variety of areas. It is virtually indestructible. A two-component copper-zinc alloy with a zinc content of not more than 20% is excellent for the manufacture of heating devices, auto parts, and sanitary equipment. Materials with a zinc part up to 40% are used to create stamped parts and accessories. Multi-component brass alloys are used much more widely than two-component ones. They are found in aircraft, ships, pipes, watches and other equipment.

Brass is widely used by jewelers to make beautiful jewelry. They call these metallic color compounds yellow, golden as well as green. The most interesting chemical option, which contains 5% aluminum and 15% zinc. Such a jewelry metal alloy has a high resemblance to gold, which is often used by scammers. The brass used in these products can show that such “gold” is in no way inferior in beauty to a real precious metal. The alloy is very malleable during machining, which allows jewelers to create unique jewelry that only a specialist can distinguish from gold. The cleaning of such jewelry masterpieces is carried out with oxalic acid. Young jewelers are trained on materials marked L62, L68, since these compositions are most similar in quality to gold.

A special kind of brass alloy with good deformation is called tompak. The zinc component of the metallic material does not exceed 10%. This brass composition is characterized by rust resistance, high ductility and very low friction. This material is well welded with steel and other precious metals. Due to the golden hue, various medals, accessories, as well as art products are made from tombac. It is perfectly processed under pressure, lends itself to gold coating, enamelling.

The casting type material is used in the production of shaped products and semi-finished products by casting. Cast brass is distinguished by the presence of additional thinners of manganese, aluminum, lead, as well as iron, tin with copper and zinc. It is difficult for a non-specialist to determine the brand from the available photos. The casting material does not rust, has excellent mechanical parameters, is resistant to friction and is easy to handle. It is used in the production of bearings, cast fittings, bushings, separators, automotive fittings and many other elements.

Sheets of automatic brass (LS59-1) are used to make numerous fasteners, watch elements, as well as other mass-produced parts. This type of alloy consists of lead, zinc, copper. It withstands the processing of parts in a high-speed way, from where it got its name. Automatic material is produced in bars, strips, sheets, as well as tapes.

How to get

The manufacture of brass is carried out in crucibles from clay of a fire-resistant type, as well as with the help of special reflective heaters. The crucibles themselves are heated in flame or shaft furnaces. The casting of the mixed alloy is carried out using special sand molds. In this case, a certain proportion of zinc evaporates, which is taken into account during the formation of the alloy.

The main difficulty in obtaining brass is the difference in the melting temperatures of the main components. This process is facilitated by adding a small amount of ready-made material to the molten mass. Depending on the desired final result, further processing of the composition is carried out. You can add additional components, carry out stamping, alloying, or give the necessary shape.

Brass classification

Brass compositions are divided into foundry and wrought. Casting with different components allows to produce a variety of parts for all areas of industrial use. Wrought materials have a high content of copper and are used for the manufacture of small products.

Depending on the content of various additives in the alloy, it is called silicon, aluminum, ferromanganese, which determines the brand. Additional substances allow the composition to obtain new qualities or improve existing characteristics. Foreign manufacturers use a different labeling of the compositions and a different content of impurities. In addition, brass material is distinguished by the scope of its main application. It can be “hour”, “marine” or other specific brass. Tompacs are widely used (with zinc up to 10%), as well as semi-tompacs, where the zinc share is in the range from 10 to 20%.

Main properties and characteristics

Copper-zinc material has the qualities inherent in its constituent metals. The color of the brass composition directly depends on its components and varies from light yellow to reddish. The melting point of the material is in the range from 880 to 950 °C, and the density is 8500 kg/m3. It is well processed under pressure at various temperature conditions. In addition, brass alloy with various components is practically not affected by the external environment, has high wear resistance and high strength.

Brass products have good mechanical properties. Unlike copper, it is more ductile and malleable, less refractory, which is very convenient for industrial processing. With a decrease in the ambient temperature, brass products do not lose their plastic properties, which is attractive for the manufacture of structural materials. Over time, the surface of the composition may darken slightly, but this does not affect the characteristics of the material. The greater the content of the copper fraction in the brass alloy, the higher its electrical and thermal conductivity. To prevent corrosion, brass parts are fired after treatment at low temperatures.

Brass is an alloy based on zinc and copper. The percentage of zinc in the alloy can be 5 - 45%. Zinc, unlike copper, is cheaper, which is why its introduction into the composition not only increases the technological, anti-friction and mechanical properties of the alloy, but also reduces its cost.

brass properties

Brass alloys excellent pressure handling. The mechanical performance is quite high, but the corrosion resistance is satisfactory. If we compare the distinctive features of brass with bronze, then its anti-friction properties, corrosion resistance and strength are lower. Alloys are not very stable in salt water, air, solutions of most organic acids and carbon dioxide solutions.

Brass, unlike copper, has better corrosion resistance. But as the temperature rises, the rate of corrosion also increases. Moreover, such a process is noticeable in products with thin walls. Corrosion can be caused by: high humidity, traces of sulfur dioxide and ammonia in the air. To prevent this phenomenon, products from this composition are subjected to low-temperature firing after processing.

Almost all alloys when the temperature drops do not become brittle and remain elastic, which allows them to be used as an excellent structural material. Due to the higher recrystallization temperature, in contrast to copper, at elevated temperatures, the creep of brass is lower. At a temperature of 300-600 C, the property of brittleness appears due to the fact that additions insoluble at low temperatures (for example: bismuth, lead) create fragile layers between the crystals. As the temperature increases, the impact strength decreases. Unlike copper, the thermal and electrical conductivity properties of brass are worse.

The composition of brass as a percentage

The main components - zinc and copper - are used in ratios of 30% and 70%, respectively.

More than 50% of the zinc used in the manufacture of brass comes from recycled waste. Technical brass alloys made of 47–50% zinc. According to the composition, alpha and beta brass are distinguished:

• Two-phase formulations are 48-50% zinc and contain less than 5% lead.
• Single-phase alpha compounds have about 30% zinc.

Chemical composition

Brass is made from copper and zinc. Often her compared to bronze, since the alloy of brass and bronze combines the same component - copper. Brass, which differs in composition from bronze, has as its second component not tin, but zinc.

Zinc is a chemical constituent element of a minor subgroup of the second group of the fourth period of the periodic system of Mendeleev. Under normal conditions rather fragile bright blue transition material (covered with a small layer of zinc oxide in the open air and darkens). In nature, as a separate metal, zinc does not exist.

Copper is a chemical constituent element of the eleventh group of the fourth period of the periodic system of Mendeleev. This is plastic transition material bright golden color (when an oxide layer appears, copper becomes red-yellow).

Due to zinc and copper (except for the main α-solution), a whole list of electronic stages of type β, γ, ε. As a rule, the composition of brass has α- or α+β' phases:

• α-phase– a stable copper and zinc material with a face-centered crystalline copper cubic lattice.
• β'-phase– a structural material based on the chemical combination of CuZn with a ratio of 3/2 and an elementary and simplest cell.

Dependence on heat treatment:

• If a high temperature, then the β-phase has a chaotic arrangement of atoms and an increased volume of a homogeneous composition. In this state, the phase becomes quite plastic, if the temperature is less than 453-469 C, then the atomic structure of copper and zinc acquires order and is indicated as β'.
• β' is more brittle and rigid, the γ-phase contains the Cu5Zn8 electronic combination.

Compositions with a single phase are characterized by increased plasticity; β'-phase is less plastic and more durable.

Separation based on the content of zinc alloy:

Brass production

Brass lends itself well to forging, malleable deformation, quite viscous, takes on different shapes under a hammer blow, is stamped into various parts or stretched into wire. The alloy is relatively ductile cast and melts at a temperature lower than that of copper.

Manufacturing process performed:

• In crucibles made of refractory clay. Crucibles are heated in flame or shaft furnaces.
• in reverberatory ovens.

During the mixing of zinc and copper, the composition is cast into pre-prepared sand molds. Some part of the zinc evaporates that must be remembered during the formation of the metal alloy.

Derivatives of brass

– type of wrought alloy. It contains zinc and copper by 2% -13% and 87-98%, respectively.

Tompac is different:

• reduced friction force;
• rust resistance;
• high elasticity.

Compositions of copper, consisting of 11-22% of zinc, are called semi-tompaks.

Tompac excellent weldable with stainless steel and other precious metals. Tompac is used for the manufacture of a combined composition of brass and steel. Thanks to its golden color, accessories, various medals and art products are made from tombac. Tompak lends itself well to enameling, gilding and pressure treatment at low and high temperatures.

- used for the manufacture of shaped products and semi-finished products using casting. Has 51-80% copper. In the role of additional elements used: aluminum, silicon, manganese, iron, lead and tin. Main differences:

• has resistance to friction with other elements;
• reduced tendency to decay of elements;
• does not rust;
• easy to handle due to the liquid consistency;
• excellent mechanical performance.

Often foundry brass used for mass production:

Automatic brass It is a lead type of alloy. It has the following composition:

• 24.3-42.8% - zinc;
• 56-76% - copper;
• 0.4-0.9% - lead.

The addition of lead during machining contributes to the appearance of loose and short chips, which reduces the wear of the separating mechanism and makes it possible to use high-speed machining of parts.

Mechanical characteristics automatic brass directly depend on its state of aggregation and components:

• cold-worked;
• soft.

This type of alloy is made in the form of:

• stripes;
• tapes;
• sheets;
• bars.

At the same time, sheets are made:

• watch parts;
• bolts;
• nuts and other mass-produced items.

How can you tell brass alloy from bronze

It is possible to distinguish brass from bronze and, in addition, to find out the exact composition only in a chemical laboratory (for example, using spectroscopic analysis). Alas, at home (especially if you can’t scratch or otherwise deform the product), the range of possibilities is rather limited. However, there is an algorithm that shows, albeit not very accurate, but still results.

You will need:

• calculator;
• accurate scales;
• transparent container with water;
• samples of brass and bronze with chips;
• microscope or strong loupe.

Start with visual analysis. It is necessary to thoroughly clean the product and place it under sunlight. Usually bronze is darker than brass, and if we consider the color, then bronze turns into a “red” spectrum (from red to brown), and brass into “yellow”, sometimes even up to white. But this method is not very inaccurate, so go to the second step.

Do a composition analysis on density. You will need a transparent container with water and an accurate scale. Having lowered the product into water, we find out the volume, then we determine the mass. Density is the ratio of the mass of an object to its volume, translated into kg / cu. m. Most often, bronze is denser than brass, while the dividing line is at 8700 kg / cu. m. So, 8400-8700 kg / cubic meter - most likely brass. 8750-8900 - most likely bronze.

And in the end, composition structure. I must say that samples are needed here - objects where both brass and bronze can be accurately determined in the composition, and the samples must have chips.

A strong magnifying glass or microscope will be needed for analysis. The analysis is carried out by placing in the field of view both the sample and the subject of analysis. What do you need to pay attention to? On the structure of the composition - namely, its grain. Usually bronze has a coarser and coarser grain than brass.

Brass

Brass- an alloy of copper and zinc (from 5 to 45%). Brass with content from 5 to 20% zinc called red (tompac), with a content of 20-36% Zn - yellow. In practice, brasses are rarely used, in which the zinc concentration exceeds 45%.

Zinc is a cheaper material compared to copper, so its introduction into the alloy, along with an increase in mechanical, technological and anti-friction properties, leads to a decrease in cost - brass cheaper than copper. Electrical conductivity and thermal conductivity brass lower than copper.

Brass- double and multicomponent copper alloy, with the main alloying element - zinc. Compared to copper, they have higher strength and corrosion resistance. Simple brass is designated by the letter L and a number showing the percentage of copper. In special brasses, after the letter L, they write the capital letter of additional alloying elements and, through a dash after the copper content, indicate the percentage of alloying elements. Brass is divided into foundry and wrought. Brass, with the exception of lead-containing brass, can be easily worked by cold and hot pressure. All brass are well soldered with hard and soft solders.

Corrosion resistance brass under atmospheric conditions, it turns out to be an average between the resistance of the elements that form the alloy, i.e. zinc and copper. Brass containing more than 20% zinc is prone to cracking when stored in a humid atmosphere (especially if traces of ammonia are present). This effect is often referred to as "seasonal cracking". It is most noticeable in deformed products, since corrosion propagates along grain boundaries. To eliminate this phenomenon, after deformation, brass is annealed at 240 - 260 (°C).

Brass have high technological properties and are used in the production of various small parts, especially where good machinability and formability are required. Good castings are obtained from them, since brass has good fluidity and a low tendency to segregation. Brass are easily plastically deformable - most of them are used for the manufacture of rolled semi-finished products - sheets, strips, tapes, wires and various profiles.

Usually brass is divided into:

two-piece brass("Simple"), consisting only of copper, zinc and, in small quantities, impurities.

For two-component brass, the phase composition of the alloy is of particular importance. The solubility limit of zinc in copper at room temperature is 39%. As the temperature rises, it decreases and at 905 °C it becomes equal to 32%. For this reason brass containing less than 39% zinc, have a single-phase structure (a-phase) of a solid solution of zinc in copper. They are called a-brasses. If more zinc is introduced into the melt, then it will not be able to completely dissolve in copper, and after solidification, a second phase will appear - (b-phase). The b-phase is very brittle and hard, so two-phase brasses have higher strength and less ductility than single-phase brasses.

With an increase in zinc concentration up to 30%, both strength and ductility increase simultaneously. Then the plasticity decreases, first due to the complication of the solid solution, then it sharply decreases, since a brittle b-phase appears in the structure of the alloy. Strength increases up to a zinc concentration of about 45% and then decreases as sharply as ductility.

Majority brass handles well with pressure. Single-phase brasses are especially plastic. They deform at low and at high temperatures. However, in the range of 300 - 700 (°C) there is a brittle zone, therefore, at such temperatures, brass does not deform.

A feature of the processing of brass by pressure is that for processing in a cold state (thin sheets, wire, calibrated profiles), a-brass with a zinc content of up to 32% is used, since it has high ductility and low strength at room temperature. With an increase in temperature to 300-700 ° C, its plasticity decreases, therefore, it is not processed in a hot state. For this purpose, either b-brass with a high zinc content (up to 39%) is used, which is capable of transferring to the a+b two-phase state when heated, or (a+b)-brass.

brand brass is made up of the letter "L", indicating the type of alloy - brass, and a two-digit figure characterizing the average copper content. For example, brand L80 - brass, containing 80% Cu and 20% Zn.

multi-component brass("Special") - in addition to copper and zinc, there are additional alloying elements

The number of grades of multi-component brass is greater than that of two-component brass. The name of the special brass reflects its composition. So, if it is alloyed with iron and manganese, then it is called "Iron-manganese", if it is alloyed with aluminum - "Aluminum", etc.

The brand of these brass are composed as follows: first, as in simple brass, the letter L is placed, followed by a series of letters indicating which alloying elements, except for zinc, are included in this brass; then numbers follow through hyphens, the first of which characterizes the average copper content in percent, and the subsequent ones characterize each of the alloying elements in the same sequence as in the letter part of the brand. The order of letters and numbers is established according to the content of the corresponding element: first comes the element, which is more, and then descending. The zinc content is determined by the difference from 100%. For example, the brand LAZhMts66-6-3-2 is deciphered as follows: brass, which contains 66% Cu, 6% Al, 3% Fe and 2% Mn. Zinc in it is 100-(66+6+3+2)=23%.

The main alloying elements in multicomponent brass are aluminum, iron, manganese, lead, silicon, nickel. They affect the properties of brass in different ways.

Manganese increases strength and corrosion resistance, especially in combination with aluminium, tin and iron.
Tin increases strength and greatly improves corrosion resistance in sea water. Brass those containing tin are often referred to as marine brasses.
Nickel increases strength and corrosion resistance in various environments.
Lead degrades mechanical properties, but improves machinability. They are alloyed (1-2%) brass, which are subjected to mechanical processing on automatic machines. Therefore, these brasses are called automatic.
Silicon degrades hardness and strength. With joint alloying with silicon and lead, the antifriction properties of brass increase and it can serve as a substitute for more expensive, for example, tin bronzes used in plain bearings.

Brass versus Bronze have lower strength, corrosion resistance and antifriction properties. They are very stable in air, sea water, solutions of most organic acids, carbon dioxide solutions.

Double wrought brass

L96 Radiator and capillary tubes
L90 Parts of machines, devices of heat engineering and chemical equipment, coils, bellows, etc.
L85 Parts of machines, devices of heat engineering and chemical equipment, coils, bellows, etc.
L80 Parts of machines, devices of heat engineering and chemical equipment, coils, bellows, etc.
L70 Sleeves of chemical equipment
L68 Stamped products
L63 Nuts, bolts, car parts, condenser pipes
L60 Thick-walled pipes, nuts, machine parts

Multi-piece wrought brasses

LA77-2 Sea vessel condenser tubes
LAZH60-1-1 Parts of marine vessels
LAN59-3-2 Parts of chemical equipment, electrical machines, marine vessels
LZhMa59-1-1 Bearing shells, parts of aircraft, marine vessels
LN65-5 Gauge and condenser tubes
LMts58- 2 Nuts, bolts, fittings, machine parts
LMtsA57- 3-1 Details of sea and river vessels
L090-1 Condenser pipes of heat engineering equipment
L070-1 The same
L062-1 The same
L060-1 Condenser pipes of heat engineering equipment
LS63-3 Watch parts, bushings
LS74-3 The same
LS64-2 Printing matrices
LS60-1 Nuts, bolts, gears, bushings
LS59-1
LS59-1V The same
LZhS58-1-1 Parts made by cutting
LK80-3 Corrosion-resistant machine parts
LMsh68-0.05 Condenser tubes
LAMsh77-2-0.05 The same
LOMsh70-1-0.05 The same
LANKMts75- 2- 2.5- 0.5- 0.5 Springs, gauge pipes

Cast brass

LTs16K4 Reinforcement parts
LTS23A6ZHZMts2 Massive worm screws, pressure screw nuts
LTSZOAZ Corrosion-resistant parts
LTs40S Cast fittings, bushings, separators, bearings
LTs40MtsZZh Critical parts operating at temperatures up to 300 °C
LTs25S2 Car hydraulic system fittings

Brass has relatively high mechanical properties and satisfactory corrosion resistance and, being the cheapest of copper alloys, is widely used in many branches of engineering.

Brass is divided into double and multicomponent. Double copper-zinc alloys - simple or double brasses, multi-component - special brasses. Double brass containing 88 - 97% copper is called tompak, and containing 79 - 80% copper - semi-tompac. The name of special brasses is given by an additional alloying element (except zinc), for example, brass containing, in addition to zinc, aluminum is called aluminum brass, etc. According to the technological principle, deformable and foundry brass are distinguished.

Semi-finished products from wrought brass are produced in the following conditions: soft (annealed), semi-hard (compression 10-30%), hard (compression more than 30%) and extra hard (compression more than 50%). Foundry brasses are smelted from both primary and secondary metals (secondary brasses).

Aluminum, silicon, tin, nickel, manganese, iron and lead are introduced into special brass as additional alloying additives. These additives (except for lead) increase corrosion resistance, strength, fluidity, grind brass grain; lead greatly improves machinability.

The chemical composition and purpose of brass, physical and mechanical properties, types of semi-finished products are given in the following tables:

Table 1. Chemical composition in% and types of semi-finished products of deformable simple brass (according to GOST 1019-47)

brand	Components		Impurities (no more)						Semi-finished products
	Cu	Zn	Pb	Fe	Sb	Bi	P	Total
L 96	95,0-97,0	O with t a l b n s e	0,03	0,10	0,005	0,002	0,01	0,2	Radiator tubes
L 90	88,0-91,0		0,03	0,10	0,005	0,002	0,01	0,2	Sheets; cladding tapes
L 85	84,0-86,0		0,03	0,10	0,005	0,002	0,01	0,3	Corrugated pipes
L 80	79,0-81,0		0,03	0,10	0,005	0,002	0,01	0,3	Sheets, tapes and wires
L70	69,0-72,0		0,03	0,07	0,002	0,002	0,005	0,2	Stripes and ribbons
L68	67,0-70,0		0,03	0,10	0,005	0,002	0,002	0,3	Strips, sheets, tapes, pipes and wires
L62	60,5-63,5		0,08	0,15	0,005	0,002	0,002	0,5	Strips, sheets, tapes, pipes, wire rods

Note:
1. In brass grade L70, in addition to the listed impurities, there can be no more than 0.005 As, 0.005 Sn and 0.002 S.
2. In anti-magnetic brass, the iron content<= 0,03%.Table 2. Physical and technological properties of simple wrought brass

brand		L 96	L 90	L 85	L 80	L 70	L 68	L 62
Melting point in °C		1070	1045	1025	1099	950	938	905
Density in g / cm 3		8,85	8,78	8,75	8,06	8,62	8,60	8,43
Modulus of elasticity in kg/mm ​​2	soft brass	-	-	-	10 600	-	11 000	10 000
	solid brass	11 400	10 500	10 500	11 400	11 200	11 500	-
Linear expansion coefficient X 10 6 1/°C		17,0	17,0	18,7	18,8	18,9	19,0	20,6
Specific heat capacity in cal/g °C		0,093	0,09	0,092	0,093	0,09	0,093	0,092
Thermal conductivity in cal/cm sec °C		0,592	0,40	0,36	0,34	0,29	0,28	0,26
Hot working temperature in °C		700-850	700-850	750-850	750-850	750-850	750-850	750-850
Annealing temperature in °C		450-650	450-650	450-650	450-650	450-650	450-650	450-650

Table 3. Chemical composition in% and types of special brass semi-finished products (according to GOST 1019-47)

Name of brass	brand	Content of components, %								Semi-finished products
		Cu	Al	sn	Si	Pb	Fe	Mn	Ni
Aluminum	LA77-2	76,0-79,0	1,75-2,50	-	-	-	-	-	-	Condenser pipes
Aluminum - ferruginous	LAZH60-1-1	58,0-61,0	0,75-1,50	-	-	-	0,75-1,50	0,1-0,6	-	Pipes and bars
Aluminum - Nickel	LAN59-3-2	57,0-60,0	2,5-3,50	-	-	-	-	-	2,0-3,0	Pipes and bars
Nickel	LN65-5	64,0-67,0	-	-	-	-	-	-	5,0-6,0	Gauge tubes, wire, sheets and tapes
ferruginous manganese	LZhMts59-1-1	57,0-60,0	0,1-0,2	0,3-0,7	-	-	0,6-1,2	0,5-0,8	-	strips, rods, wire and pipes
manganese	LMts58-2	57,0-60,0	-	-	-	-	-	1,0-2,0	-	Strips, rods, wires and sheets
Manganese - aluminum	LMtsA57-5-1	55,0-58,0	0,5-1,5	-	-	-	-	2,5-3,5	-	Forgings
Tin tompak	LO90-1	88,0-91,0	-	0,25-0,75	-	-	-	-	-	Stripes and ribbons
Tin	LO70-1 LO62-1 LO60-1	69,0-71,0 61,0-63,0 59,0-61,0	- - -	1,0-1,5 0,7-1,1 1,0-1,5	- - -	- - -	- - -	- - -	- - -	Pipes Rods, sheets and strips Welding wire
lead	LS74-3 LS64-2 LS63-3 LS60-1 LS59-1 LS59-1V	72,0-75,0 63,0-66,0 62,0-65,0 59,0-61,0 57,0-60,0 57,0-61,0	- - - - - -	- - - - - -	- - - - - -	2,4-3,0 1,5-2,0 2,4-3,0 0,6-1,0 0,8-1,9 0,8-1,9	- - - - - -	- - - - - -	- - - - - -	Strips, tapes, rods for watchmaking bars Sheets, strips, ribbons, rods, wire, pipes bars
Ferrous - lead	LZhS58-1-1	56,0-58,0	-	-	-	0,7-1,3	0,7-1,3	-	-	bars
Siliceous	LK80-3	79,0-81,0	-	-	2,5-4,0	-	-	-	-	Forgings and stampings

Table 4. Basic physical, mechanical and technological properties of special brasses

900

brand	Density g/cm2	Coefficient linear expansion 10 6 , 1 °C	Melting temperature °C	Warmly- conductivity kN/cm sec	Specific electro- resistance ohm mm 2 /m	Elastic modulus kg/mm ​​2	σ kg/mm ​​2	δ %	Hot working temperature °C	Annealing temperature °C
LA 77-2	8,6	18,3	1000	0,27	0,075	-	38	50	700-770	600-650
LAJ 60-1-1	8,2	21,6	904	-	0,09	10 500	42	50	700-800	600-700
LAN 59-3-2	8,4	19,0	956	0,20	0,078	10 000	50	42	700-800	600-650
LN 65-5	8,7	18,2	960	0,14	0,146	11 200	38	65	750-870	600-650
LZhMts 59-1-1	8,5	22,0	900	0,24	0,093	10 600	45	50	650-750	600-650
LMts 58-2	8,5	21,2	880	0,17	0,118	10 000	44	36	650-750	600-650
LMC A 57-3-1	-	-	-	-	-	-	52	30	650-750	600-700
LO 90-1	8,8	18,4	1015	0,30	0,054	10 500	28	50	700-800	550-650
LO 70-1	8,5	19,7	935	0,22	0,072	10 600	35	60	650-750	550-650
LO 62-1	8,5	19,3	906	0,26	0,072	10 000	38	40	700-750	550-650
LO 60-1	8,4	21,4	0,24	0,070	10 500	38	40	750-800	550-650
LS 74-3	8,7	19,8	965	0,29	0,078	10 500	35	45	-	600-650
LS 64-2	8,5	20,3	910	0,28	0,066	10 500	34	55	-	600-650
LS 63-3	8,5	20,5	905	0,28	0,066	10 500	35	45	-	600-650
LS 60-1	8,5	20,8	900	0,25	0,064	10 500	35	50	-	600-650
LS 59-1	8,5	20,6	900	0,25	0,68	10 500	42	45	640-780	600-650
LK 80-3	8,6	17,0	900	0,1	0,2	9 800	34	55	750-850	500-600

Table 5. Mechanical properties and assortment of brass sheets and strips (according to GOST 931-52 and 6688-53)

Type, dimensions and condition of semi-finished products	Brass brand	σ, kg/mm ​​2	δ, %	Punching depth according to Eriksen (punch with a diameter of 100 mm) with sheet thickness, mm
				0,4-0,45	0,5	0,6-0,1	1,2-1,5
Cold-rolled soft sheets and strips: sheet dimensions: thickness 0.4-10 mm, width and length 600x1500, 710x1410 and 1000x2000 mm; strip dimensions: thickness 0.4-10 mm, width 40-500 mm	L 68 L62 LMts 58-2 Ls 59-1	30 30 39 35	40 40 30 25	>= 10 >= 9,5 - -	>= 11 >= 9,5 - -	>= 11,5 >= 10,0 - -	>= 12,5 >= 10,5 - -
Sheets and strips semi-solid	L 68 L 62 LMts 58-2	36 35 45	25 20 25	8-10 7-9 -	9-11 7-9 -	9,5-11,5 7,5-9,5 -	11-13 8-10 -
Sheets and strips cold-rolled solid	L 68 L 62 LMts 58-2 LO 62-1 LS 59-1	40 42 60 40 45	15 10 3 5 6	7-9 5-7 - - -	7-9 5-7 - - -	7,5-9,5 5,5-7,5 - - -	- - - - -
The strips are extra hard	L 62	60	2,5	-	-	-	-
Hot-rolled sheets: thickness 5-22 mm, width and length 600x1500, 710x1410 and 1000x2000 mm	L 62 LO 62-1 LS 59-1	30 35 35	30 20 25	- - -	- - -	- - -	- - -
Stripes (thickness 1.5x8.0 mm, width 20-90 mm); LS 63-3	soft semi-solid solid extra hard	30 35-44 60 64	40 - 6 >= 5	- - - -	- - - -	- - - -	- - - -
Rectangular pressed strips from 5x20 to 25x60 in size	L 62 LZhMts59-1-1 LMts58-2 LO 62-1 LS 59-1	30 44 43 35 38	30 31 25 25 21	- - - - -	- - - - -	- - - - -	- - - - -

6. Mechanical properties of brass strips (according to GOST 2208-49)

Brass brand	Material condition	σ, kg/mm ​​2	δ, %	Depth of punching according to Eriksen (punch with a diameter of 10 mm) with a thickness of the tapes, mm
				Up to 0.25	0,3-0,55	0,6-1,1	1,2-1,6	1,7-2,0
L 68 L 62 LM 58-2 LS 59-1 LS 63-3*	Soft	30 30 39 35 30	40 35 30 25 40	>= 9 >= 7,5 - - -	>= 11 >= 9,5 - - -	>= 11,5 >= 10 - - -	>= 12 >= 10,5 - - -	>= 12,5 >= 11,0 - - -
L 68 L62 LMts 58-2 LS 63-3*	semi-solid	35 38 45 35-44	25 20 25 -	7-9 5,5-7,5 - -	9-11 7,5-9,5 - -	9,5-11,5 8-10 - -	10-12 8,5-10,5 - -	10,5-12,5 9-11 - -
L 68 L62 LS 59-1 LMts 58-2 LS 63-3*	solid	40 42 45 60 44-54	15 10 5 3 6	5-7 3-5 - - -	7-9 5,5-7,5 - - -	7,5-9,5 6-8 - - -	- - - - -	- - - - -
L 68 l 62 LS 63-3	extra hard	50 60 64	4 2,5 >= 5	- - -	- - -	- - -	- - -	- - -

* According to GOST 4442-48.

Table 7. Mechanical properties of round, square or hexagonal brass bars (according to GOST 2060-60)

Brass brand	Bar condition	Diameter of round or diameter of inscribed circle square and hexagonal bars in mm	σ, kg/mm ​​2	δ, %	Application area
			at least
L 62	drawn Pressed	5-40 10-160	38 30	15 30
LS 59-1	drawn Pressed	10-160 5-40	30 40	30 12	In all branches of mechanical engineering
LS 63-3	Drawn (solid) drawn Semi-solid	5-9,5 10-14 15-20	60 55 50	1 1 1	For watch parts
LO 62-1	drawn Pressed	5-40 10-160	40 37	15 20	In marine shipbuilding
ЛЖС 58-1-1	drawn Pressed	5-40 10-160	45 30	10 20	For watch parts
LMts 58-2	drawn Pressed	5-12 13-40	45 42	20 20	in shipbuilding
LZhMts 59-1-1	drawn Pressed	5-12 St. 12-40	50 45	15 17	in shipbuilding
LAJ 60-1-1	Pressed	10-160	45	18	In aircraft construction

Table 8. Mechanical properties of brass wire (according to GOST 1066-58)

Brass brand	Wire diameter in mm	σ in in kg/mm ​​2 wire in condition			δ in % at wire condition
		soft	semi-solid	solid	soft	semi-solid	solid
L 68	0,10-0,18 0,20-0,75 0,80-1,4 1,50-12	38 35 32 30	- 40 38 35	70-95 70-95 60-80 55-75	20 25 30 40	- 5 10 15	- - - -
L 62	0,1-0,18 0,20-0,50 0,55-1,0 1,10-4,8 5-12	35 35 35 35 32	- 45 45 40 36	75-95 70-95 70-90 60-80 55-75	18 20 26 30 34	- 5 5 10 12	- - - - -
LS 59-1	2-4,8 5-12	35 35	40 40	45-65 45-65	30 30	- -	5 8

Table 9. Mechanical properties and assortment of brass pipes (according to GOST 494-52)

Brass brand	Name, condition and dimensions of pipes	σ in in kg / mm 2	δ in %
L 62 L 68 LO 70-1	Pipes drawn soft with a diameter of 3-100 mm	30 30 30	30 30 30
L 62 L 68 LO 70-1	Semi-solid drawn pipes	34 35 35	30 30 30
L 62 LS 59-1 LZhMts 59-1-1	Pipes pressed with a diameter of 21-195 mm	30 40 44	38 20 28
L 96*	Hexagonal and round radiator tubes	35-60	-
L 96**	Soft capillary tubes with an inner diameter of 0.35-0.50 mm and an outer diameter of 1.2-2.5 mm	-	-
L 80***	Thin-walled tubes for bellows with a diameter of 8-80 mm, wall thickness 0.07-0.6 mm	-	-

* According to GOST 529-41, ** According to GOST 2624-44, *** According to GOST 5685-51.

Table 10. Composition, mechanical properties and purpose of foundry brasses (according to GOST 1019-47)

0,8-1,0

Brass brand	Chemical composition								Density g/cm 3	Mechanical properties		Purpose
	Cu	Al	Fe	Mn	Si	sn	Pb	Zn		σ in g/mm 2	δ %
LA67-2.5	66-68	2-3	-	-	-	-	-	O with t a l b n about e	8,5	40(kg) 30(kg)	15(kg) 12(kg)	For the manufacture of corrosion-resistant parts
LAZhMts66-6-3-2	64-68	6-7	2,0-4,0	1,5-2,5	-	-	-		8,5	65(k) 60(h) 70(c)	7(k) 7(h) 7(c)	For making nuts, jack screws, worm screws and other heavy duty parts
LAZH60-1-1L	58-61	0,75-1,5	0,75-1,5	1,0-0,6	-	0,2-0,7	-		8,5	42(k) 98(d)	18(k) 20(h)	For the manufacture of armature bushings and bearing shells
LK80-3L	79-81	-	-	-	2,5-4,5	-	-		8,5	30(k) 25(h)	15(k) 10(h)	For the manufacture of fittings and other parts in shipbuilding
LKS 80-3-3	79-81	-	-	-	2,5-4,5	-	2,0-4,0		8,5	30(k) 25(h)	15(k) 7(h)	For the manufacture of bearing shells and bushings
LMts58-2-2	57-60	-	-	1,5-2,5	-	-	1,5-2,5		8,5	35(k) 25(h)	8(k) 10(h)	For the manufacture of bushing bearing shells and other anti-friction parts
LMtsOS58-2-2-2	56-60	-	-	1,5-2,5	-	1,5-2,5	0,5-2,5		8,5	30(k) 30(h)	4(k) 6(h)	For making gears
LMtsZh55-2-1	53-58	-	0,5-1,5	3-4	-	-	-		8,5	50(k) 45(d)	10(k) 15(h)
LMtsZh82-4-1	50-55	-	0,5-1,5	4-5	-	-	-		8,5	50(k) 50(k)	15(k) 15(k)	Bearings and fittings
LS59-1L	57-61	-	-	-	-	-	8,5		20(k)	20(c)	Bushings for ball bearings

Note:
Legend:
k - casting in a chill mold,
h - casting into the ground,
c - centrifugal casting.

Table 11. Physical and mechanical properties of foundry brasses

Basic properties	Brass brand
	LA 67-2.5	LAZhMts66-3-3-2	LAZh60-1-1l	LC80-3l	LKS80-3-3	LMtsS56-2-2	LMtsOS58-2-2-2-2	LMtsZh52-4-1	LMtsZh55-3-4	LS59-1-l
Liquidus temperature in °С	995	899	904	900	900	890	890	870	880	885
Coefficient of linear expansion x 10 -6, 1/°С	-	19,8	21,6	17	17	21	-	-	22	20,1
Thermal conductivity in cal/cm sec °C	0,27	0,12	0,27	-	-	0,26	0,26	-	0,24	0,26
σ in in kg / mm 2 at: 20 °C 200 °С 300 °С 400 °С	35 - - -	65 - - -	40 - - -	40 40 40 30	35 - - -	36 40 33 24	35 - - -	50 50 34 32	50 - - -	35 37 26 23
δ 10 in % at: 20 °C 200 °С 300 °С 400 °С	15 - - -	7 - - -	20 - - -	20 22 17 17	20 - - -	20 20 22 24	6 - - -	20 - 24 28	- - - -	40 43 - 28
σ T in kg / mm 2	-	-	25	16	14	24	-	30	-	15
α n in kgm / cm 2	-	-	-	12	4	7,0	-	-	-	2,6
Hardness HB	90	-	90	105	95	80	95	120	105	85
Linear shrinkage in %	-	-	-	1,7	1,7	1,8	-	1,7	1,6	2,23
Friction coefficient paired with axial steel: with lubrication without lubrication	- -	- -	- -	0,01 0,19	0,009 0,15	0,16 0,24	- -	- -	- -	0,013 0,17

Table 12. Chemical composition in% and marking of secondary brasses (according to GOST 1020-60)

brand	Cu	Al	Pe	Mn	Si	Ni	sn	Pb	Zn	Marking ingots with paints
LA	0,3-0,8	2-3	-	-	-	-	-	-	O with t a l b n about e	Two white stripes
LAZhMts	63-68	6-7	2,0-4,0	1,5-2,5	-	-	-	-		two blue stripes
LAJ	56-61	0,75-1,5	0,1-0,6	-	-	0,2-0,7	-	-		One green stripe and one red stripe
OK	70-81	-	-	-	2,5-4,5	-	-	-		two red stripes
LKS	70-81	-	-	-	2,5-4,5	-	-	2-4		One red stripe and one blue stripe
LMtsS	55-60	-	-	1,5-2,5	-	-	-	1,5-2,5		One green stripe and one blue stripe
LMcOS	55-60	-	-	1,5-2,5	-	-	1,5-2,5	0,5-2,5		Two black stripes
LMWC1	53-58	-	0,5-1,5	3-4	-	-	-	-		two green stripes
LMWC2	50-55	-	0,5-1,5	4-5	-	-	-	-		One black stripe and one white stripe
LS	56-61	-	-	-	-	-	-	0,8-1,9		One red stripe and one white stripe
VOC	60-80	-	-	-	-	-	0,5-2,0	1,0-3,0		Three red stripes
LNMCJA	58-62	0,5-1,0	0,5-1,1	1,5-2,5	-	0,5-1,5	-	-		Three white stripes

Brass is the oldest alloy, since its manufacture dates back to the time of the Roman Empire. At that time, it was the first metal in value after silver and gold. Due to its composition, it has an attractive appearance and at the same time high strength. Pleasant to the eye golden-yellowish color gives copper, and the addition of zinc and other components makes it a strong material.

Composition of brass

In the formula of brass, two components will always be unchanged - copper and zinc. Copper is a natural resource, zinc is mined by recycling waste. In the finished material, the mass of zinc is kept in the range from 5 to 50%.

Copper is number 29 in the periodic table, has a high plasticity, has a beautiful yellowish-golden color. When interacting with open air, an oxide film appears on the metal, due to which the copper turns red.

Zinc, which is number 30 in the periodic table, is a brittle metal and has a light blue color, darkens when an oxide film appears.

Copper-zinc alloy is divided into single-phase and two-phase:

• Single phase alloy contains about 30% zinc. This is a common composition, which is characterized by plasticity and at the same time hardness. If the percentage of zinc increases, then the ductility decreases while the hardness of brass increases. After reaching the zinc mark of 40%, the hardness index immediately drops. Single-phase brass belongs to ductile alloys and can be processed both at low temperatures and at elevated ones, however, at a temperature of 400C, a brittle zone appears.
• Dual Phase Alloy consists of 30-50% zinc and has impurities of other metals within 10%. This is a technical or special alloy. It does not differ in plasticity, only when heated above 700C it acquires plastic properties.

Types of brass

Brass is simple and special:

1. Simple- It contains only two components, copper and zinc. Marked with the letter "L" and numbers. The numbers in the marking indicate the percentage of copper to the total mass of the alloy. Based on this, it is clear that the alloy marked "L68", has 68% copper and 32% zinc.
2. Special- consists not only of copper and zinc, other metals are added to it, which change the properties of the alloy depending on their characteristics. The marking of this material carries information about the percentage of copper to zinc and other elements, which are called alloying. For example, marking "LA70−3" indicates that the composition used 70% copper, 3% aluminum and 27% zinc. In special brass, additional metals can be:

• Tin.
• Lead.
• Iron.
• Manganese.
• Nickel.
• Silicon.
• Aluminum.

Brass production, types and properties

Brass is produced at high temperatures in special clay containers. In the manufacture of the alloy, it must be taken into account that part of the zinc evaporates.

The alloy is divided into several types:

1. Tompac is an alloy containing no more than 13% zinc. Tompac is characterized by increased elasticity, high resistance to rust and abrasion. This type of brass is used when welding with stainless steel to obtain a valuable alloy, from which medals, accessories, jewelry, art products and tools are subsequently made.
2. Semi-tompak- this is an alloy in which zinc varies between 10-20%. The scope of semi-tompak is similar to tompak, but it is a less valuable alloy.
3. Cast brass is an alloy containing 50-80% copper, as well as impurities of other metals. Due to its fluid properties, it is used in the manufacture of semi-finished products and shaped products by casting. Possesses low indicators of disintegration of materials, is steady against friction and a rust also possesses excellent mechanical properties. Cast brass is used in the production of bushings, fittings, nuts, bearings and other rust-resistant fittings.
4. Automatic brass is an alloy containing lead, in percentage terms not exceeding 0.8%. Lead allows you to increase the speed of processing products due to the formation of short chips. It is produced in the form of sheets, tapes and rods, later they are used to grind clockwork parts, hardware and nuts.

Often enough brass is confused with bronze, and many even believe that this is the same material - this is fundamentally wrong. You can also distinguish these two metals at home, for this you need to go through the following algorithm of actions:

1. It is good to clean both materials and examine them in sunlight. The color of bronze will go to red, and brass to yellow, sometimes even white.
2. By placing the product in a container of water, you can analyze the density. The molar mass of brass is in the range of 8350−8750 kg/m3, if the mass is higher, then it is bronze.

Application of brass

This copper-zinc material is malleable and viscous, thanks to these qualities it is actively used in forging, mechanical engineering and other fields. Under the impact of an anvil or hammer, brass takes on any shape. Depending on the scope of brass, the composition of the alloy as a percentage changes in accordance with the following marking:

1. L80, L85, L90, L96 - elements of devices, chemical and heat engineering mechanisms, coils, etc.
2. L68 - stamped parts.
3. L70 - quill for the chemical industry.
4. L60 - thick-walled fittings, machine givers and nuts.
5. L63 - elements for the automotive industry, condenser tubes.
6. LAZH60−1−1 - spare parts for marine vessels.
7. LA77−2 - capacitor devices for marine vessels.
8. LAN59−3−2 - elements of chemical equipment, marine vessels and electrical machines.
9. LN65−5 - condenser and manometric pipes.
10. LZhMa59−1−1 - spare parts for aircraft and marine vessels, bearing shells.
11. LMts58−2 - hardware, nuts, fittings.
12. LO90−1, LO62−1, LO70−1, LO06−1 - condenser tubes for heat engineering equipment.
13. LMtsA57−1−1 - elements and spare parts for river and sea vessels.
14. LS74−3, LS63−3 - bushings and watch movements.
15. LK80−3 - corrosion-resistant products.
16. LANKMts75−2−2.5−0.5−0.5 - springs and manometric pipes.
17. LMsh68−0.05 - capacitor collectors.

Brass remains the most sought after and popular alloy, whatever its composition. Subject to the production technology, it will not rust, blacken and oxidize.

Brass is a high-temperature compound of copper and zinc melts. To impart various properties to the melt, depending on the direction of the use of brass, various additives are added during its smelting. It is known that an alloy of copper and tin is called bronze, but tin can also serve as an additive in the smelting of brass. Its name depends on the quantitative predominance of zinc or tin in a copper alloy: more tin - bronze, more zinc - brass. The properties of the latter alloy are determined by additives added to the melt in much smaller quantities - these are substances such as metals: iron, lead and nickel, and non-metals: silicon and phosphorus.

Although zinc was obtained in the form of a metal only in the sixteenth century, but received brass even before the beginning of the modern reckoning, when melting, adding rich zinc ore - galmey (a mixture of zinc spar with the formula ZnCO 3 and zinc silicic acid) to the copper melt. The method of obtaining brass was patented by an English metallurgist at the end of the seventeenth century. And already in the nineteenth century in the Western part of Russia and Europe, gold jewelry was falsified by means of brass.

Properties

From copper, brass inherited a significant specific gravity, depending on the content of the main component in brass, its density ranges from 8.3 to 8.7 tons per cubic meter. In general, many the physical properties of brass as an alloy depend on the ratio of its components, not only the main ones, but also those added in small quantities - alloying.

Perhaps, a more or less stable characteristic is the specific heat capacity, its indicator at room temperature is 380 J / (kg * K), which means that it takes 380 Joules of heat to heat a metal weighing one kilogram by one degree Kelvin. The specific electrical resistance varies from 0.025 to 0.108 Ohm*sq. mmm. The melting point of brass also varies widely, from 870 to 990 degrees Celsius. Copper is a more refractory metal than zinc, so lower values ​​apply to alloys with a higher zinc content.

Brass works well contact welding, but not fusion welded, it is easy to roll. To protect the metal from oxidation in air, its surface is varnished to prevent blackening, although brass is more weatherproof than copper. Brass has a golden color and it lends itself well to polishing. Additives to the alloy of bismuth and lead reduce its crumpling in a heated state, but improve the behavior of the alloy when processed by a cutting tool.

The content in the zinc alloy determines such important properties as strength and ductility - these two seemingly mutually exclusive concepts. If zinc is added up to thirty percent, then along with this, the characteristics of strength and ductility increase. After this threshold, ductility begins to decrease, and strength continues to increase up to 45%, then decreases, as well as ductility.

Many brands of brass lend themselves well to pressure treatment both at low temperatures and in a heated state, with the exception of temperatures from 300 to 700 degrees, which is a brittle zone and the alloy does not deform in this temperature range. Improving the mechanical and chemical characteristics of brass, they additionally include alloying additives.

How alloying additives affect

An alloying agent is an addition to an alloy., changing its composition and, as a result, giving it some new properties, or increasing or decreasing existing properties. To reduce the loss of metal from the surface of the melt, aluminum is added to the resulting oxide film, and plays a protective role. To increase strength and improve anti-corrosion properties, magnesium is added to the alloy, either separately or together with aluminum and iron. Moreover, additives practically do not affect the density of the metal.

Nickel melt additive eliminates the manifestation of negative aspects in terms of oxidative processes. It is possible to improve the ductility, malleability of the alloy and the conditions for its cutting by introducing an additive such as lead into the composition of brass. Silicon combined with lead improves glide to such an extent that an alloy alloyed with this additive can be used on an equal footing with tin bronze. At the same time, silicon, added without other additives, specifically increases the hardness and strength of brass. If the metal is to be used on a ship, tin is added to make it resistant to salt water.

Marking

In metal marking adhere to certain rules set out in state standards - GOST. The alloy is designated with the initial letter - L, then the initial letters of the alloy additives with numbers indicating the amount of the additive go. Marked deformable brass after the first letter includes numbers - how much copper is in the composition: L 70.

If the wrought brass is also alloyed, the initial letter of the additives is added to the designation, and the number as a percentage: LAN 60-1-1, this is 60% copper, 1% aluminum and 1% nickel. The zinc content in such an alloy is calculated by the difference, in this 100 - (60 + 1 + 1) = 38%. Brass for casting is marked differently: the quantitative values ​​of the alloy components are entered immediately after their first letters. So, in the product LC 40 Mts 1 zinc 40%, manganese 1%.

Scopes of brass

Worldwide consumption of zinc for the production of this alloy is estimated at two million tons, with half of this amount represented by scrap zinc products. Brass for technical purposes obtained by fusing approximately equal amounts of copper and zinc. All brass products can be divided into three main types that determine the direction of their application:

• deformable- contain less than ten percent zinc, their second name is tompak, it has good ductility, does not corrode and glides well on metal. It has excellent weldability with steel and an excellent color shade - like gold;
• foundry- their name speaks of the main direction of application, the production of objects by casting, they consist of 50-80% of copper. The alloy is resistant to corrosion, does not deform when rubbed against other metals, is very durable and not brittle. In the melt, it is easy to pour it into molds of any configuration;
• submachine gun- these are lead-added alloys, this combination makes it possible for discrete chips to exit from under the cutter, which is very important when processing products in an automated position - the wear of machine parts is reduced and the processing speed increases.

One of the most sought after metals in the world is brass. The use of this alloy affects almost all sectors of the national economy. Simple alloys with an addition of zinc within 20% are used for the manufacture of machine parts and mechanisms, heat exchangers.

On the manufacture of stamped items go alloys with the inclusion of zinc up to 40%, and if such alloys are alloyed with additives, they are used in shipbuilding and mechanical engineering, aircraft building and construction, in the watch industry, etc. Art objects, various jewelry and other attributes, including signs are made from tombak military distinction.

Cast brass is a material for the manufacture of parts operating in an aggressive environment. Hardware is made from the automatic machine - screws, including self-tapping screws, nuts with bolts and studs. The alloy is non-magnetic, it is used where this property is in demand, for example, for the manufacture of compass parts. The increased heat capacity determines its use in thermal appliances, so samovars have long been made of brass. Church utensils are another area of ​​application for this golden alloy.

In jewelry brass is valued no less than the noble metals that it imitates in the manufacture of jewelry and bijouterie. Specialists divide brass products into three groups:

The color closest to the color of gold is brass with fifteen percent zinc and an aluminum additive in the amount of 5%. Often this property is used by dishonest people, forging gold jewelry, although the density of gold and fakes are incomparable. Clean brass items with oxalic acid.