Mechanical characteristics of amg2m and amg2n. Aluminum alloys

ALUMINUM ALLOYS

Alloy classification

Physical properties

Corrosive properties

Mechanical properties

Round and profile aluminum products

Flat rolled aluminum

Classification of aluminum alloys.

Aluminum alloys are conventionally divided into casting (for the production of castings) and wrought (for the production of rolled products and forgings). Further, only wrought alloys and rolled products based on them will be considered. Rolled aluminum means rolled products made from aluminum alloys and technical aluminum (A8 – A5, AD0, AD1). The chemical composition of wrought alloys for general use is given in GOST 4784-97 and GOST 1131.

Wrought alloys are divided according to hardening method: strengthened by pressure (deformation) and heat-strengthened.

Another classification is based on key properties: alloys of low, medium or high strength, high ductility, heat-resistant, forging, etc.

The table systematizes the most common wrought alloys with a brief description of the main properties inherent in each system. Marking is given in accordance with GOST 4784-97 and international classification ISO 209-1.

Characteristics of alloys	Marking		Alloying system	Notes
ALLOYSPRESSURE STRENGTHENED (THERMAL-RESTRIFIED)
Low strength alloys And high plasticity,	AD0	1050A	Tech. aluminum without alloying	Also AD, A5, A6, A7
	AD1	1230
	AMts	3003	Al –Mn	Also MM (3005)
	D12	3004
Medium strength alloys And high plasticity, weldable, corrosion-resistant	AMg2	5251	Al –Mg (Magnalia)	Also AMg0.5, AMg1, AMg1.5AMg2.5 AMg4, etc.
	AMg3	5754
	AMg5	5056
	AMg6
HEAT-HARDENABLE ALLOYS
Medium strength alloys and high ductility weldable	AD31	6063	Al-Mg-Si (Aviali)	Also AB (6151)
	AD33	6061
	AD35	6082
Alloys normal strength	D1	2017	Al-Cu-Mg (Durali)	Also B65, D19, VAD1
	D16	2024
	D18	2117
Weldable alloys of normal strength	1915	7005	Al-Zn-Mg
	1925
High strength alloys	B95		Al-Zn-Mg-Cu	Also B93
Heat-resistant alloys	AK4-1		Al-Cu-Mg-Ni-Fe	Also AK4
	1201	2219	Al-Cu-Mn	Also D20
Forging alloys	AK6		Al-Cu-Mg-Si
	AK8	2014

Delivery states Pressure hardenable alloys, are strengthened only by cold deformation (cold rolling or drawing). Strain hardening leads to an increase in strength and hardness, but reduces ductility. Restoration of plasticity is achieved by recrystallization annealing. Rolled products from this group of alloys have the following delivery states, indicated in the labeling of the semi-finished product:

without heat treatment

2) M - annealed

3) H4 - quarter cold hardened

4) H2 - semi-hardened

5) H3 - 3/4 cold-worked

6) N - hard-worked

Semi-finished products from heat-strengthening alloys strengthened by special heat treatment. It consists of hardening at a certain temperature and subsequent holding for some time at a different temperature (aging). The resulting change in the structure of the alloy increases strength and hardness without loss of ductility. There are several heat treatment options. The most common delivery conditions for heat-strengthening alloys are the following, reflected in the marking of rolled products:

1) does not have a designation - after pressing or hot rolling without heat treatment

2) M - annealed

3) T - hardened and naturally aged (for maximum strength)

4) T1 - hardened and artificially aged (for maximum strength)

For some alloys, thermomechanical hardening is carried out when cold hardening is carried out after hardening. In this case, TN or T1H is present in the marking. Other aging modes correspond to states T2, T3, T5. Usually they correspond to lower strength, but higher corrosion resistance or fracture toughness.

The given state markings correspond to Russian GOST standards.

Physical properties of aluminum alloys.

The density of aluminum alloys differs slightly from the density of pure aluminum (2.7g/cm 3). It varies from 2.65 g/cm 3 for the AMg6 alloy to 2.85 g/cm 3 for the V95 alloy.

Alloying has virtually no effect on the elastic modulus and shear modulus. For example, the modulus of elasticity of strengthened duralumin D16T is almost equal to the modulus of elasticity of pure aluminum A5 ( E =7100 kgf/mm 2). However, due to the fact that the yield strength of the alloys is several times higher than the yield strength of pure aluminum, aluminum alloys can already be used as a structural material with different levels of loads (depending on the grade of the alloy and its condition).

Due to the low density, the specific values of the tensile strength, yield strength and elastic modulus (the corresponding values divided by the density value) for strong aluminum alloys are comparable to the corresponding specific values for steel and titanium alloys. This allows high-strength aluminum alloys to compete with steel and titanium, but only up to temperatures not exceeding 200 C.

Most aluminum alloys have poorer electrical and thermal conductivity, corrosion resistance, and weldability compared to pure aluminum.

The table below shows the values of hardness, thermal and electrical conductivity for several alloys in various states. Since hardness values correlate with the values of the yield strength and tensile strength, this table gives an idea of the order of these values.

The table shows that alloys with a higher degree of alloying have noticeably lower electrical and thermal conductivity; these values also significantly depend on the state of the alloy (M, H2, T or T1):

brand	hardness, NV			electrical conductivity in % relative to copper			thermal conductivity in cal/o C
brand	M	H2	N,T(T1)	M	H2	N, T(T1)	M	H2	N, T(T1)
A8 - AD0	25		35	60			0.52
AMts	30	40	55	50	40		0.45	0.38
AMg2	45	60		35		30	0.34		0.30
AMg5	70			30			0.28
AD31			80	55		55	0.45
D16	45		105	45		30	0.42		0.28
B95			150			30			0.28

The table shows that only AD31 alloy combines high strength and high electrical conductivity. Therefore, “soft” electrical busbars are made from AD0, and “hard” ones from AD31 (GOST 15176-89). The electrical conductivity of these buses is (in µOhm*m):

0.029 – from AD0 (without heat treatment, immediately after pressing)

0.031 – from AD31 (without heat treatment, immediately after pressing)

0.035 – from AD31T (after hardening and natural aging)

The thermal conductivity of many alloys (AMg5, D16T, V95T1) is half that of pure aluminum, but it is still higher than that of steels.

Corrosive properties.

The alloys AMts, AMg, AD31 have the best corrosion properties, and the worst are the high-strength alloys D16, V95, AK. In addition, the corrosion properties of heat-strengthened alloys significantly depend on the quenching and aging regime. For example, alloy D16 is usually used in a naturally aged state (T). However, above 80 o C, its corrosion properties deteriorate significantly and artificial aging is often used for use at high temperatures, although it corresponds to lower strength and ductility (than after natural aging). Many strong heat-strengthenable alloys are susceptible to stress corrosion and exfoliation corrosion.

Weldability.

AMts and AMg alloys are well welded by all types of welding. When welding cold-worked steel, annealing occurs in the weld zone, so the strength of the weld corresponds to the strength of the base material in the annealed state.

Of the heat-hardening alloys, aviation and alloy 1915 are well welded. Alloy 1915 is self-hardening, so the weld acquires the strength of the base material over time. Most other alloys can only be welded by spot welding.

Mechanical properties.

The strength of AMts and AMg alloys increases (and ductility decreases) with increasing degree of alloying. High corrosion resistance and weldability determine their use in light-duty structures. AMg5 and AMg6 alloys can be used in moderately loaded structures. These alloys are strengthened only by cold deformation, therefore the properties of products made from these alloys are determined by the state of the semi-finished product from which they were made.

Heat-strengthening alloys make it possible to harden parts after their manufacture if the original semi-finished product has not been subjected to heat-strengthening treatment.

The greatest strength after hardening heat treatment (quenching and aging) are alloys D16, V95, AK6, AK8, AK4-1 (of those available in the public market).

The most common alloy is D16. At room temperature, it is inferior to many alloys in terms of static strength, but has the best structural strength (crack resistance). Usually used in a naturally aged state (T). But above 80 C its corrosion resistance begins to deteriorate. To use the alloy at temperatures of 120-250 C, products made from it are subjected to artificial aging. It provides better corrosion resistance and higher yield strength compared to the naturally aged state.

With increasing temperature, the strength properties of alloys change to varying degrees, which determines their different applicability depending on the temperature range.

Of these alloys, up to 120 C, V95T1 has the greatest strength and yield limits. Above this temperature it is already inferior to the D16T alloy. However, it should be taken into account that V95T1 has significantly worse structural strength, i.e. low crack resistance compared to D16. In addition, B95 in T1 condition is susceptible to stress corrosion. This limits its use in tensile products. Improved corrosion properties and a significant improvement in crack resistance are achieved in products processed according to T2 or T3 modes.

At temperatures of 150-250 C, D19, AK6, AK8 have greater strength. At high temperatures (250-300 C), it is advisable to use other alloys - AK4-1, D20, 1201. Alloys D20 and 1201 have the widest temperature range of use (from cryogenic -250 C to +300 C) under high load conditions.

Alloys AK6 and AK8 are ductile at high temperatures, which allows them to be used for the manufacture of forgings and stampings. Alloy AK8 is characterized by greater anisotropy of mechanical properties, it has lower crack resistance, but it welds better than AK6.

The listed high-strength alloys are poorly weldable and have low corrosion resistance. Weldable heat-strengthening alloys with normal strength include alloy 1915. This is a self-hardening alloy (allows hardening at a natural cooling rate), which allows for high strength of the weld. Alloy 1925, while not differing from it in mechanical properties, is welded worse. Alloys 1915 and 1925 have greater strength than AMg6 and are not inferior to it in terms of weld characteristics.

Medium-strength alloys - aviali (AB, AD35, AD31, AD33) are well welded and have high corrosion resistance.

ROLLED ALUMINUM.

All types of rolled products are produced from aluminum and its alloys - foil, sheets, strips, plates, rods, pipes, wire. It should be borne in mind that for many heat-strengthening alloys there is a “press effect” - the mechanical properties of pressed products are higher than those of hot-rolled ones (i.e., circles have better strength indicators than sheets).

Rods, profiles, pipes

Rods made of heat-hardening alloys are supplied in a state “without heat treatment” or in a hardened state (hardening followed by natural or artificial aging).Rods made from thermally non-hardening alloys are produced by pressing and supplied in a state “without heat treatment”.

A general idea of the mechanical properties of aluminum alloys is given by a histogram, which shows guaranteed indicators for extruded rods at normal temperatures:

Of all the above varieties, rods made of D16 are always available for free sale, and circles with a diameter of up to 100 mm inclusive are usually supplied in a naturally aged state (D16T). The actual values (according to quality certificates) for them are: yield strength? 0.2 = (37-45), tensile strength ? in = (52-56), relative elongation ? =(11-17%). The machinability of D16T rods is very good; for D16 rods (without heat treatment) the machinability is noticeably worse. Their hardness is 105 HB and 50 HB, respectively. As already noted, a part made of D16 can be strengthened by hardening and natural aging. Maximum strength after hardening is achieved on the 4th day.

Since the D16 duralumin alloy does not have good corrosion properties, additional protection of products made from it by anodizing or applying paint and varnish coatings is desirable. When operating at temperatures above 80-100 C, a tendency to intergranular corrosion appears.

The need for additional protection against corrosion also applies to other high-strength alloys (D1, V95, AK).

Rods made of AMts and AMG have high corrosion resistance and allow the possibility of additional shaping by hot forging (in the range of 510-380 o C).

A variety of profiles are widely presented from AD31 alloy with various heat treatment options. They are used for structures of low and medium strength, as well as for decorative products.

Rods, pipes and profiles made from AD31 have high overall corrosion resistance and are not prone to stress corrosion. The alloy is well welded by spot, roller and argon-arc welding. The corrosion resistance of the weld is the same as that of the base material. To increase the strength of the weld, special heat treatment is necessary.

Angles are made mainly from AD31, D16 and AMg2.

Pipes are made from most of the alloys shown in the figure. They are supplied in unheated (pressed), hardened and aged, and annealed and cold-worked states. The parameters of their mechanical properties approximately correspond to those shown in the histogram. When choosing a pipe material, in addition to its strength characteristics, its corrosion resistance and weldability are taken into account. The most accessible pipes are made from AD31.

Availability of circles, pipes and angles - see on the website page "Aluminum circles, pipes and angles"

Flat rolled aluminum.

General purpose sheets are produced in accordance with GOST 21631-76, tapes - in accordance with GOST 13726-97, plates in accordance with GOST 17232-99.

Sheets made of alloys with reduced or low corrosion resistance (AMg6, 1105, D1, D16, VD1, V95) are clad. The chemical composition of the cladding alloy usually corresponds to the AD1 grade, and the layer thickness is 2–4% of the nominal sheet thickness.

The cladding layer provides electrochemical protection of the base metal from corrosion. This means that corrosion protection of the metal is provided even in the presence of mechanical damage to the protective layer (scratches).

Sheet marking includes: alloy grade designation + delivery condition + type of plating (if present). Marking examples:

A5 - sheet of grade A5 without plating and heat treatment

А5Н2 - sheet of grade A5 without plating, semi-coloured

AMg5M - Amg5 grade sheet without plating, annealed

D16AT - sheet of grade D16 with normal plating, hardened and naturally aged.

The histogram shows the main characteristics of the mechanical properties of sheets in various states of delivery for the most used grades. The "no heat treatment" condition is not shown. In most cases, the values of the yield strength and ultimate strength of such rolled products are close to the corresponding values for the annealed state, and the ductility is lower. The slabs are produced in the “without heat treatment” state.

It can be seen from the figure that the produced range of sheets provides ample opportunities for choosing a material in terms of strength, yield strength and ductility, taking into account corrosion resistance and weldability. For critical structures made of strong alloys, crack resistance and fatigue resistance characteristics must be taken into account.

Sheets of technical aluminum (AD0, AD1, A5-A7).

Cold-worked and semi-hardened sheets are used for the manufacture of unloaded structures and tanks (including for cryogenic temperatures), which require high corrosion resistance and allow the use of welding. They are also used for the manufacture of ventilation ducts, heat-reflecting screens (the reflectivity of aluminum sheets reaches 80%), and insulation of heating mains.

Sheets in a soft state are used to seal permanent joints. The high plasticity of annealed sheets allows the production of products by deep drawing.

Technical aluminum is highly resistant to corrosion in many environments (see page " Properties of aluminum"). However, due to the different content of impurities in the listed brands, their anti-corrosion properties still differ in some environments.

Aluminum can be welded using all methods. Technical aluminum and its welded joints have high corrosion resistance to intergranular and exfoliating corrosion and are not prone to corrosion cracking.

In addition to sheets manufactured in accordance with GOST 21631-76, sheets produced in accordance with the European standard, marked 1050A, are available for free sale. In terms of chemical composition, they correspond to the AD0 brand. The actual parameters (according to quality certificates) of mechanical properties are (for sheets 1050AN24): yield strength ? 0.2 = (10.5-14), tensile strength ? V=(11.5-14.5), relative elongation ? =(5-10%), which corresponds to a semi-hardened state (closer to cold-hardened). Sheets marked 1050AN0 or 1050AN111 correspond to the annealed state.

1105 alloy sheets (and strips).

Due to reduced corrosion resistance, it is manufactured clad. Widely used for insulation of heating mains, for the manufacture of lightly loaded parts that do not require high corrosion properties.

AMts alloy sheets.

Sheets made of AMts alloy are well deformed in cold and hot states. Due to their low strength (low yield strength), they are used for the manufacture of only lightly loaded structures. The high plasticity of annealed sheets allows them to be used to produce low-load products by deep drawing.

In terms of corrosion resistance, AMts is practically not inferior to technical aluminum. They are well welded by argon-arc, gas and resistance welding. The corrosion resistance of the weld is the same as that of the base metal.

Sheets made of AMg alloys.

The higher the magnesium content in the alloys of this group, the stronger they are, but less ductile.

Mechanical properties.

The most common sheets are made of AMg2 (states M, N2, N) and AMg3 (states M and N2) alloys, including corrugated ones. Alloys AMg1, AMg2, AMg3, AMg4 are well deformed in both hot and cold states. The sheets have satisfactory stampability. Cold-pressing significantly reduces the stampability of sheets. Sheets of these grades are used for structures with medium load.

Sheets made of AMg6 and AMg6 in a hardened state are not supplied. Used for heavy-duty structures.

Corrosion resistance. AMG alloys are characterized by high corrosion resistance in solutions of acids and alkalis. Alloys AMg1, AMg2, AMg3, AMg4 have high corrosion resistance to the main types of corrosion both in the annealed and cold-worked state.

Alloys AMg5, AMg6 are prone to stress corrosion and intergranular corrosion. To protect against corrosion, sheets and plates made of these alloys are clad, and AMg5p rivets are used only anodized.

Weldability.

All AMg alloys can be welded well by argon arc welding, but the characteristics of the weld depend on the magnesium content. As its content increases, the cracking coefficient decreases and the porosity of welded joints increases.

Welding cold-worked sheets eliminates cold-working in the heat-affected zone of the welded joint; the mechanical properties in this zone correspond to the properties in the annealed state. Therefore, welded joints of cold-worked AMg sheets have lower strength compared to the base material.

Welded joints AMg1, AMg2, AMg3 are highly resistant to corrosion. To ensure corrosion resistance of the weld seam AMg5 and AMg6, special heat treatment is required.

Sheets and slabs from D1, D16, B95.

High-strength alloys D1, D16, V95 have low corrosion resistance. Since sheets made from them are used for structural purposes, they are clad with a layer of technical aluminum for corrosion protection. It should be remembered that technological heating of clad sheets made of alloys containing copper (for example D1, D16) should not even briefly exceed 500 C.

The most common sheets are made of D16 duralumin. The actual values of mechanical parameters for sheets made of D16AT (according to quality certificates) are: yield strength ? 0.2 = (28-32), tensile strength ? V= (42-45), relative elongation ? =(26-23%).

Alloys in this group are spot welded, but not fusion welded. Therefore, the main way to connect them is with rivets. For rivets, wire from D18T and B65T1 is used. The shear resistance for them is 200 and 260 MPa, respectively.

Plates of D16 and B95 are available from thick sheets. The slabs are supplied in a state “without heat treatment”, but it is possible to heat strengthen the finished parts after their manufacture.The hardenability of D16 allows heat strengthening of parts with a cross section of up to 100-120 mm. For B95 this figure is 50-70 mm.

Sheets and slabs made of B95 have greater (compared to D16) compressive strength.

Availability of sheets and plates - see on the website page "Aluminum sheets"

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The properties of general-purpose aluminum alloys are briefly discussed above. For special purposes, either other alloys or purer versions of the D16 and V95 alloys are used. To imagine the variety of special alloys used in aircraft and rocketry, it is worth visiting the websitehttp://

We offer unclad aluminum sheet AMg2 with a smooth and corrugated surface. Rolled sheets are produced in accordance with GOST 21631-76. Chemical composition of aluminum alloy grade AMg2 according to GOST 4784-74. Types of corrugation: diamond and quintet. Wide range of sizes. Sale from a warehouse in Moscow or to order in the shortest possible time.

Service

Deliveries of deformable aluminum alloy grade AMg2 are carried out in sheets and rolls. Favorable prices for domestic and foreign high-quality rolled products. Individual approach to every customer. Professional services for grinding, anodizing, bending and cutting aluminum sheets to size. Temporary anti-corrosion protection, packaging, transportation and storage in accordance with GOST 9.510-93.

Characteristics

Aluminum sheet AMg2 has good corrosion resistance, ductility and weldability. The number 2 in the marking of a wrought alloy indicates the percentage of magnesium.

According to the condition of the material:

annealed aluminum sheet AMg2M;
cold hardened aluminum sheet AMg2N.

Heat treatment changes the structure of the material, its physical and mechanical properties. As a result of annealing, AMg2M sheets become more ductile and malleable. The machinability of the product by cutting is significantly improved. To partially restore the hardness of the metal, tempering is used - rolling with a reduction of 2-5%. High-strength AMg2N sheets are produced by cold pressure working. This reduces the ductility and impact strength of the material. Aluminum sheet AMg2N2 is made from an alloy cold-worked to one half. It combines good strength and mechanical properties. Aluminum sheets AMg2NR are made from cold-worked and refined alloy. The minimum content of impurities allows improving the electrical conductivity of semi-finished products.

By production method:

unclad aluminum sheets.

Matte surface with normal finishing quality. Normal manufacturing accuracy in thickness, width and length.

Scope of application

AMg2M and AMg2N sheets are used for the manufacture of building structures and transport parts. They are used to make hydraulic equipment, industrial pipelines, truck linings, and chemical pressure vessels.

Chemical composition in % of AMg2 alloy
Fe	up to 0.4
Si	up to 0.4
Mn	0,2 - 0,6
Ti	up to 0.1
Al	95,3 - 98
Cu	up to 0.1
Mg	1,8 - 2,8
Zn	up to 0.2

Production of rolled products (pipes) from AMg2 alloy (and similar) by drawing method: For drawing, a pipe blank obtained by pressing or rolling on CPT mills is used. In the latter case, mainly only mandrelless drawing is carried out in order to obtain pipes of the required diameter and eliminate the characteristic rolling defect - waviness. The diameter of the workpiece from the CPT mills is 85–16 mm, the wall thickness is from 5 to 0.35 mm, the thickness difference is 10%. The blank for drawing, obtained by pressing on horizontal or vertical presses, is used for mandrel and non-mandrel drawing. The diameter of the workpieces is from 360 to 20 mm, the wall thickness is at least 1.5 mm, the thickness difference is 20%. In order to reduce the number of transitions during drawing and expensive intermediate annealing, they strive to obtain a wall thickness of the pressed billet as close as possible to the finished pipe. This is prevented by an increase in specific pressures and low productivity during pressing, as well as an increase in the relative thickness difference of the pressed workpiece above 20%. The latter is especially important, since during drawing the relative thickness difference practically does not decrease.

Before drawing, the workpiece is cleaned, sorted and cut to the required length, taking into account the length of the grip, end trim and technological allowance for the accuracy of the nominal wall thickness (from 100 to 300 mm). After cutting the pipes, the defects are cleaned out and the grips are forged using a pneumatic hammer, forging rollers, crank forging or rotary forging machines.

Hoods for pipe drawing

The optimal draw values can vary greatly for pipes of the same alloy, which is explained by a variety of factors operating under production conditions. The higher the production culture, the smaller the range of spread of extreme values of optimal extracts.

The figure on the left shows a graph showing the scatter field of the values of the integral indicator of optimal hoods, obtained under production conditions. As can be seen from this figure, the scatter is quite large and must be taken into account.

Therefore, below are averaged values of optimal draws when drawing pipes made of aluminum alloys. Along with frequent stretching per transition, total stretching from annealing to annealing is also carried out.

Brief designations:
σ in	- temporary tensile strength (tensile strength), MPa	ε	- relative settlement at the appearance of the first crack, %
σ 0.05	- elastic limit, MPa	J to	- ultimate torsional strength, maximum shear stress, MPa
σ 0.2	- conditional yield strength, MPa	σ izg	- ultimate bending strength, MPa
δ5,δ 4,δ 10	- relative elongation after rupture, %	σ -1	- endurance limit during bending test with a symmetric loading cycle, MPa
σ compress0.05 And σ compress	- compressive yield strength, MPa	J-1	- endurance limit during torsion test with a symmetrical loading cycle, MPa
ν	- relative shift, %	n	- number of loading cycles
s in	- short-term strength limit, MPa	R And ρ	- electrical resistivity, Ohm m
ψ	- relative narrowing, %	E	- normal modulus of elasticity, GPa
KCU And KCV	- impact strength, determined on a sample with concentrators of the types U and V, respectively, J/cm 2	T	- temperature at which properties were obtained, degrees
s T	- proportionality limit (yield strength for permanent deformation), MPa	l And λ	- thermal conductivity coefficient (heat capacity of the material), W/(m °C)
HB	- Brinell hardness	C	- specific heat capacity of the material (range 20 o - T), [J/(kg deg)]
H.V.	- Vickers hardness	p n And r	- density kg/m 3
HRC uh	- Rockwell hardness, scale C	A	- coefficient of thermal (linear) expansion (range 20 o - T), 1/°С
HRB	- Rockwell hardness, scale B	σ t T	- long-term strength limit, MPa
HSD	- Shore hardness	G	- modulus of elasticity during torsional shear, GPa

Aluminum is widely used in industry due to its high thermal conductivity, resistance to corrosion, ductility, low density and electrical resistance. And if you need to buy non-ferrous rolled metal, you should know that the price of this material will be the lowest compared to others.

Varieties of aluminum and its alloys

In most cases, aluminum is used in the form of alloys - 20% cast and 80% wrought. Based on the brand, you can determine the method of its production, as well as its main properties.

This metal can be divided into several main categories:

primary (A999, A95, A7E A6, etc.);
technical (AD000, AD1, ADS);
for deoxidation (AV97F, AV86, AV91);
foundry (AMg11, VAL10M, AK12pch);
deformable (D1, 1105, AMg2, SvAMg6);
antifriction (AMK, ASM, AO9-2B);
alloys (AlBi3, AlZr5(B), AlNi10 and others).

How is the marking deciphered?

Deformable alloys are designated accordingly - AD. If there is a 1 after the abbreviation, it means that purer aluminum was used. The letter A in combination with Mts and Mg is an alloy with manganese or magnesium. The number after the marking indicates the percentage content of a particular chemical element. AK is aluminum for forging, and the number at the end is the alloy number.

In semi-finished products, the main abbreviation is followed by letters (for example, AMtsAM), which are deciphered as follows:

A - high-quality alloy, made from pure grades of aluminum;
B - rolled products with technological plating or without it at all;
UP - with thickened plating;
M - soft;
N - hard-worked;
P - semi-hardened;
H1 - heavily cold-hardened;
B - high-quality rolling out of aged and pre-hardened sheets;
О - high quality of rolling out annealed sheet metal;
GK - hot rolled steel;
TPP - hardened, aged rolled steel of increased strength.

The abbreviation AL means that it is cast aluminum. Depending on the heat treatment modes, it is designated T, after which the following numbers may appear in the stamps:

8 - hardened and softened tempered;
7 - hardening with stabilizing tempering;
6 - hardening and aging to the highest hardness;
5 - hardening and partial aging;
4 - hardened;
2 - annealed;
1 - aged.

“D” in the main marking is duralumin. Designation type B or VD (alcledes) - indicates that duralumin is coated with a layer of pure aluminum in order to increase corrosion resistance. High-strength alloys with magnesium and zinc are marked “B” and a number (for example, 96 or 94), the 2nd digit of which indicates the alloy number.

Physical characteristics	Values
Elastic modulus E, MPa (kgf/cm2), at temperature, °C:

from minus 40 to plus 50

Shear modulus G, MPa (kgf/cm2). at temperature, °C:

from minus 40 to plus 50

Transverse strain ratio (Poisson) g
Linear expansion coefficient а, °С "", at temperatures from minus 70 to plus 100°С
Average density R, kg/m

Note. For intermediate temperatures the values E And G should be determined by linear interpolation.

Table 3

Aluminum Density

Table 4

Aluminum semi-finished products used for building structures

Aluminum grade		Semi-finished products

Note. The “+” sign means that this semi-finished product is used for building structures; the “-” sign means that this semi-finished product is not used.

APPENDIX 2

Mandatory

LONGITUDINAL BENDING COEFFICIENTS OF CENTRALLY COMPRESSED ELEMENTS

In table 1 shows cross-sectional diagrams for which in table. 2 and 3 of this appendix show the values of the coefficient .

Table 1

Section diagrams for determining the coefficient

table 2

Buckling coefficients of centrally compressed elements for sections of type 1

Flexibility of elements

AD31T; AD31T4

AD31T1; AMg2H2

Table 3

Buckling coefficients of centrally compressed elements for sections of type 2

Flexibility of elements	Coefficients for elements made of aluminum grades
		AD31T; AD31T4	AD31T1; AMg2H2

APPENDIX 3

Mandatory

DETERMINING THE COEFFICIENT FOR CHECKING THE GENERAL STABILITY OF BEAMS

1. For I-section beams with two axes of symmetry, to determine the coefficient, it is necessary to calculate the coefficient using the formula

(1)

where is the coefficient determined from the table. 1 and 2 of this appendix depending on the nature of the load and parameter. For pressed I-beams, the parameter should be calculated using the formula

(2)

Where - moment of inertia during torsion (here b i and t i-respectively, the width and thickness of the rectangles forming the section);

l ef - design length of the beam, determined in accordance with clause 4.13.

In the presence of round thickenings (bulbs)

Where D - bulb diameter;

P - number of bulbs in cross section.

For welded and riveted I-beams in the absence of flanges, thickenings at the edges and significant thickenings in the corners, the parameter should be determined by the formula

(3)