GOST 4784 aluminum and wrought aluminum alloys. Aluminum and aluminum alloys wrought

19.11.2019

This brand of aluminum alloy belongs to the Al-Mg-Mn group - deformable and fairly ductile alloys. Similar properties appear already at room temperature, while at elevated temperatures, the AMg6 alloy demonstrates excellent weldability and average strength characteristics. Being thermally unstrengthened, it is most widely used in the production of bimetallic sheets.

Chemical composition of AMg6 (according to GOST 4784-97)

Chemical elements that make up the alloy grade AMg6 (in percentage):

Al - 91.1-93.68%
Mg - 5.8-6.8%
Mn - 0.5-0.8%
Fe - no more than 0.4%
Si - no more than 0.4%
Zn - no more than 0.2%
Ti - 0.02-0.1%
Cu - no more than 0.1%
Be - 0.0002-0.005%

Alloy AMg6: physical and mechanical properties

While the density of the AMg6 alloy ( specific gravity) is 2640 kg/m 3 , it is endowed with relatively low hardness: HB 10 -1 =65MPa. The yield strength of AMg6, depending on the temperature and type of rolled products, can vary within 130-385 MPa.

What determines the characteristics of the AMg6 alloy? Thanks to the manganese contained in the alloy, the material is endowed with enhanced mechanical properties. In this case, after cold deformation of the workpiece, the part is strengthened even more. With the use of welding, the AMg6 alloy somewhat loses its strength properties, therefore, rivets or other fasteners are used to fasten hard-worked parts.

AMG6 is an alloy much stronger than AMG2 or AMG3, therefore it is quite suitable for stamping parts that experience static loads. Relatively low stress does not lead to cracking of the material, so AMg6 aluminum often becomes the best option to create medium-loaded welded and riveted structures, among other things, requiring high corrosion resistance.

The AMG6 alloy is widely used by the aerospace industry: such aluminum is used to produce huge fuel tanks. Do not do without aluminum of this brand and the automotive industry, and chemical, and in general mechanical engineering. AMg6 includes ship bulkheads, railway car bodies, suspended ceilings, and containers for various liquids.

Aluminum deliveries to enterprises are made in various forms: pipes, profiles, sheets, stampings of required sizes and shapes. Usually such semi-finished products are already in the annealed state.

Such alloys are called duralumins, and durals are used as structural alloys in the aviation and space industries, due to their strength and relative lightness. Sale of rolled aluminum .

In its pure form, D16 is rarely used, since in an unhardened state it has less strength and hardness than AMg6 and at the same time is inferior to it in terms of corrosion resistance and weldability. But parts from D16 with a cross section of no more than 100-120 mm can be hardened and aged after they are manufactured. In most cases, semi-finished products already hardened and aged by a natural method, marked D16T, are on sale.

The alloy is classified as a tough heat-strengthened alloy, but is not intended for welding. However, it can be welded spot welding, although in most cases parts from it are fixed with fasteners. Also, fasteners themselves can be made from D16 in the form of rivets with an anti-corrosion coating. The alloy is easily processed by cutting.

Material properties D16

D16 is a heat-strengthened wrought aluminum alloy, which has a chemical composition according to GOST 4784-97.

Due to its low thermal and electrical conductivity, this material performs well at temperatures above 120 °C and up to 250 °C, but it is not allowed to use it even for a short time at temperatures above 500 °C. It is not prone to cracking, but when the temperature rises above 80 °C, it is prone to the formation of intergranular corrosion, which imposes certain restrictions on its use. However, artificial aging avoids the formation of corrosion, with a simultaneous decrease in strength and ductility.

D16T has high hardness and strength, but is inferior in these parameters to blanks made of VD95T1 alloy in a particularly hard state after artificial aging and hardening. But when the temperature rises above 120 °C, D16T exhibits better mechanical properties and is unmatched up to 250 °C. In addition, it should be noted that VD95 is prone to stress corrosion, so it is not always possible to use the full potential of this material to the end.

Most alloys tend to corrode more than other aluminum alloys. For this reason, products made of duralumin are clad with a 2-4% layer of technical aluminum, or varnished. However, given the sometimes high temperature conditions work of parts made of duralumin, in most cases plating and anodizing are preferable, which affects the choice of sheet products manufactured under plating. In addition, D16T is difficult to weld and can only be welded by spot welding, therefore, in most cases, it is fixed with rivets and other detachable and one-piece joints.

Release form

As mentioned earlier, D16 in its pure form, although it is used, but rarely. And the low resistance to corrosion dictates the need for cladding of rolled metal. Accordingly, semi-finished products from D16 are produced in the following types:

in its purest form,
T - hardened and naturally aged,
T1 - artificially aged state.
M - annealed,
Clad (approx. D15TA)

From D16 produce:

Bars up to 100 mm in diameter are produced naturally aged in T condition, sometimes annealed - M, and sheets - clad in M or T condition, depending on the application.

Application area

D16T is a structural heat-strengthened and naturally aged alloy in a billet, which is used in various areas of the national economy.

It is also used for the manufacture of power structural elements in aircraft: skin parts, frame, frames, ribs, control rods, spar.

Also, parts operating at a temperature in the range of 120-230 ° C are also produced from it - in accordance with GOST.

It is also used in the automotive industry for the manufacture of bodies, pipes and other sufficiently strong parts.

D16T is used for the manufacture of rivets with high shear strength. The same rivets are used to fasten other softer aluminum parts, for example, from AMg6 magnals.

GOST 4784-97

INTERSTATE STANDARD

ALUMINUM ALUMINUM ALLOYS
DEFORMABLE

Stamps

INTERSTATE COUNCIL
ON STANDARDIZATION, METROLOGY AND CERTIFICATION

Minsk

Foreword

1. DEVELOPED by OJSC "All-Russian Institute of Light Alloys" (VILS), Interstate Technical Committee MTK 297 "Materials and semi-finished products from light and special alloys".

INTRODUCED by Gosstandart of Russia

2. ADOPTED by the Interstate Council for Standardization, Metrology and Certification (Minutes No. 12-97 of November 21, 1997)

State name	Name of the national standardization body
The Republic of Azerbaijan	Azgosstandart
Republic of Armenia	Armstate standard
Republic of Belarus	State Standard of Belarus
The Republic of Kazakhstan	State Standard of the Republic of Kazakhstan
Kyrgyz Republic	Kyrgyzstandart
The Republic of Moldova	Moldovastandard
Russian Federation	Gosstandart of Russia
The Republic of Tajikistan	Tajik State Standard
Turkmenistan	Main State Inspectorate of Turkmenistan
The Republic of Uzbekistan	Uzgosstandart
	State Standard of Ukraine

3. Tables 1-6 show the grades and chemical composition of aluminum and aluminum alloys, taking into account the requirements of the interstate standard ISO 209-1-89 "Wrought aluminum and aluminum alloys. Chemical composition and types of products. Part 1. Chemical composition."

4. By the Decree of the State Committee of the Russian Federation for Standardization and Metrology dated December 8, 1998 No. 433, the interstate standard GOST 4784-97 was put into effect directly as state standard Russian Federation since July 1, 2000

5. REPLACE GOST 4784-74

6. RE-ISSUE

INTERSTATE STANDARD

ALUMINUM ALLOYS ALUMINUM wrought

Stamps

Aluminum and wrought aluminum alloys. grades

Introduction date 2000-07-01

1 area of use

This standard applies to aluminum and wrought aluminum alloys intended for the manufacture of semi-finished products (tapes in rolls, sheets, discs, plates, strips, bars, profiles, tires, pipes, wire, forgings and stamped forgings) by hot or cold deformation, as well as slabs and ingots.

2. Regulatory references

GOST 1131-76 Wrought aluminum alloys in ingots. Specifications.

GOST 7871-75 Welding wire from aluminum and aluminum alloys. Specifications.

GOST 13726-97 Tapes made of aluminum and aluminum alloys. Specifications.

GOST 21631-76 Aluminum and aluminum alloy sheets. Specifications.

GOST 8617-81 Profiled from aluminum and aluminum alloys. Specifications

GOST 15176-89 Pressed spikes for electrical purposes from aluminum and aluminum alloys. Specifications

GOST 17232-99 Aluminum and aluminum alloy plates. Specifications

GOST 18475-82 Cold-formed pipes made of aluminum and aluminum alloys. Specifications

GOST 18482-79 Pressed pipes from aluminum and aluminum alloys. Specifications

GOST 21488-97 Bars pressed from aluminum and aluminum alloys. Specifications

GOST 22233-2001 Profiled aluminum alloys for translucent enclosing structures. Specifications

GOST 23786-79 Drill pipes made of aluminum alloys. Specifications.

3. General requirements

Grades and chemical composition of aluminum must correspond to those indicated in table 1.

3.1. The ratio of iron and silicon in aluminum must be at least one.

3.2. The grades and chemical composition of aluminum alloys of the aluminum-copper-magnesium and aluminum-copper-manganese systems should correspond to those indicated in table 2.

3.3. The grades and chemical composition of aluminum alloys of the aluminum-manganese system must correspond to those indicated in table 3.

3.3.1. The ratio of iron and silicon in the AMtsS alloy must be greater than one.

3.4. Grades and chemical composition of aluminum alloys of the aluminum-magnesium system must correspond to those indicated in table 4.

3.4.1. In the AMg2 brand alloy, intended for the manufacture of a tape used as a packaging container in Food Industry, the mass fraction of magnesium should be from 1.8 to 3.2%.

3.5. Grades and chemical composition of aluminum alloys of the aluminum-magnesium-silicon system must correspond to those indicated in table 5.

3.6. The grades and chemical composition of aluminum alloys of the aluminum-zinc-magnesium system must correspond to those indicated in table 6.

3.7. In aluminum and aluminum alloys listed in tables 1-6, partial or complete replacement of titanium with boron or other modifying additives that provide a fine-grained structure is allowed.

3.8. In aluminum and aluminum alloys, semi-finished products from which are used in the manufacture of food products, the mass fraction of lead should be no more than 0.15%, the mass fraction of arsenic - no more than 0.015%. Markia-aluminum and aluminum alloys for food purposes are additionally marked with the letter "Sh".

(Changed edition. Rev. No. 1).

3.9. The chemical composition of alloys of grades D1, D16, AMg5 and V95, intended for the manufacture of wire for cold heading, must correspond to that indicated in Table 7. In this case, the brand is additionally marked with the letter "P".

3.10. The grades and chemical composition of aluminum and aluminum alloys intended for the manufacture of welding wire must correspond to those indicated in Table 8.

3.12. The chemical composition of aluminum and aluminum alloys in tables 1-8 is given as a percentage by weight. The calculated value, or the value obtained from the analysis, shall be rounded in accordance with the rounding rules given in Annex A.

3.13. The column "Other elements" includes elements, the content of which is not presented, as well as elements not indicated in the tables.

3.14. The calculation of other elements includes mass fractions of elements expressed to the second decimal place and equal to 0.01% or more.

3.15. The mass fraction of beryllium is determined by the calculation of the charge, is not determined, but is provided by the production technology.

3.16. In analysis protocols chemical composition a generalized conclusion is given on the compliance of the content of other elements with the requirements of GOST 4784, based on their single values and the sum of the values of these elements.

Foreword

1. DEVELOPED by JSC "All-Russian Institute of Light Alloys" (VILS), Interstate Technical Committee MTK 297 "Materials and semi-finished products from light and special alloys"

INTRODUCED by Gosstandart of Russia

2. ADOPTED by the Interstate Council for Standardization, Metrology and Certification (Minutes No. 12 of November 21, 1997)

State name	Name of the national standardization body
The Republic of Azerbaijan	Azgosstandart
Republic of Armenia	Armstate standard
Republic of Belarus	State Standard of Belarus
The Republic of Kazakhstan	State Standard of the Republic of Kazakhstan
Kyrgyz Republic	Kyrgyzstandart
The Republic of Moldova	Moldovastandard
Russian Federation	Gosstandart of Russia
The Republic of Tajikistan	Tajik State Standard
Turkmenistan	Main State Inspectorate of Turkmenistan
The Republic of Uzbekistan	Uzgosstandart
	State Standard of Ukraine

Amendment No. 1 adopted by the Interstate Council for Standardization, Metrology and Certification (Minutes No. 23 dated May 22, 2003)

The national standardization bodies of the following states voted for the adoption of the change: AZ, AM, BY , GE , KZ, KG , MD , RU, TJ , TM , UZ, UA [alpha-2 codes according to MK (ISO 3166) 004]

6. EDITION (August 2009) with Amendment No. 1 approved in November 2003 (IUS 2-2004), Amendments (IUS 11-2000, 5-2004, 4-2005)

GOST 4784-97

INTERSTATE STANDARD

ALUMINUM AND ALUMINUM ALLOYS

Stamps

Aluminum and wrought aluminum alloys. grades

Introduction date 2000-07-01

1 area of use

This standard applies to aluminum and wrought aluminum alloys intended for the manufacture of semi-finished products (strips in rolls, sheets, discs, plates, strips, bars, profiles, tires, pipes, wire, forgings and stamped forgings) by hot or cold deformation, as well as slabs and ingots.

Section 2 (Deleted, Rev. No. 2).

3. General requirements

Grades and chemical composition of aluminum must correspond to those indicated in the table.

3.1. The ratio of iron and silicon in aluminum must be at least one.

3.2. The grades and chemical composition of aluminum alloys of the aluminum-copper-magnesium and aluminum-copper-manganese systems must correspond to those indicated in the table.

(Changed edition, Rev. No. 1; Amendments, IUS 11-2000, 5-2004).

3.3. The grades and chemical composition of aluminum alloys of the aluminum-manganese system must correspond to those indicated in the table.

(Revised edition, Rev. No. 1).

3.3.1. The ratio of iron and silicon in the AMtsS alloy must be greater than one.

3.4. The grades and chemical composition of aluminum alloys of the aluminum-magnesium system must correspond to those indicated in the table.

(Revised edition, Rev. No. 1).

3.4.1. In the AMg2 grade alloy intended for the manufacture of tape used as packaging in the food industry, the mass fraction of magnesium should be from 1.8 to 3.2%.

3.5. The grades and chemical composition of aluminum alloys of the aluminum-magnesium-silicon system must correspond to those indicated in the table.

(Revised edition, Rev. No. 1; Amendment, IUS 11-2000).

3.6. The grades and chemical composition of aluminum alloys of the aluminum-zinc-magnesium system must correspond to those indicated in the table.

(Revised edition, Rev. No. 1).

3.7. In aluminum and aluminum alloys indicated in the tables -, partial or complete replacement of titanium with boron or other modifying additives that provide a fine-grained structure is allowed.

Grades of aluminum and aluminum alloys for food use are additionally marked with the letter "Ш".

(Revised edition, Rev. No. 1).

3.9. The chemical composition of alloys of grades D1, D16, AMg5 and V95, intended for the manufacture of wire for cold heading, must correspond to that indicated in the table. In this case, the brand is additionally marked with the letter "P".

3.10. The grades and chemical composition of aluminum and aluminum alloys intended for the manufacture of welding wire must correspond to those indicated in the table.

The grades and chemical composition of aluminum alloys of the aluminum-silicon system must correspond to those indicated in the table.

(Amendments, IUS 11-2000, 4-2005).

3.12. The chemical composition of aluminum and aluminum alloys in the tables is given as a percentage by weight. The calculated value or the value obtained from the analysis is rounded in accordance with the rounding rules given in the appendix.

3.10 - 3.12 (Revised edition, Rev. No. 2).

3.13. The column "Other elements" includes elements, the content of which is not presented, as well as elements not indicated in the tables.

3.14. (Deleted, Rev. No. 3).

3.15. The mass fractions of beryllium, boron and cerium are set according to the calculation of the charge, are not determined, but are provided by the production technology.

(New edition, Change No. 2).

3.16. The content of other elements is not determined (provided by production technology). The content of each of the other elements and their amount in the protocols for the analysis of the chemical composition are not indicated

(New edition, Rev. No. 3).

D16t characteristics and decoding of the brand, aluminum alloy D16t density, GOST and other information.

One of the most popular duralumin alloys in the shipbuilding, aviation and space industries. Its main advantage lies in the fact that the rolled metal obtained from it has:

stable structure;
high strength characteristics;
3 times lighter weight than steel products;
increased resistance to microscopic deformation during operation;
good machinability on lathes and milling machines, second only to some other aluminum alloys.

In this regard, the products do not require additional heat treatment and avoid such a common problem as reducing the size of workpieces after natural or artificial hardening, which is typical for products made from D16 alloy.

Alloy d16t: brand decoding

The chemical composition of duralumin D16T strictly regulated GOST 4784-97 and decrypted as follows:

D - duralumin;
16 - alloy number in the series;
T - hardened and naturally aged.

Duralumin D16T refers to aluminum alloys of the Al-Cu-Mg system alloyed with manganese. Most of it is aluminum - up to 94.7%, the rest is copper, magnesium and other impurities. Manganese increases the corrosion resistance of the alloy and improves its mechanical properties, although it does not form common strengthening phases with aluminum, but only dispersed particles of the Al12Mn2Cu composition.

Iron inclusions, which do not dissolve in aluminum, negatively affect the characteristics of d16t. Ferrum crystallizes in a duralumin alloy in the form of rough plates, significantly reducing its strength and ductility parameters. In addition, iron impurities bind copper, as a result of which the strength of the alloy decreases, reaching maximum values after natural aging. In this regard, its content in duralumin is very strictly limited by GOST and should not exceed the mass fraction - 0.5-0.7%.

In the West there is an analogue of the alloy D16T, whose density is also equal to 2.78 g/sq. see, but marked differently - 2024 t3511.

Heat treatment of alloy d16t

Duralumin D16T is subjected to additional processing to improve its performance:

First of all, temperature hardening is carried out at 495-505 degrees. At higher temperatures, aluminum burns out, leading to a sharp decrease in quality characteristics alloy.
Secondly, duralumin is hardened in cold water, and the temperature of the cooling water has a great influence. The most optimal range at which the alloy reaches its maximum resistance to intergranular corrosion and pitting is 250-350 degrees.
And lastly, the D16T duralumin alloy undergoes natural aging, which is carried out at room temperature for 4-5 days.

As a result, after hardening and aging, the material acquires a hardness of 125-130 HB, which is the highest among all known duralumins.

Scope of rolled products D16T

Due to its high strength, hardness and lightness, alloy D16T used for the manufacture of various metal products. It is in demand in various industrial areas:

in the structures of aircraft and ships and spacecraft;
for the manufacture of parts for machines and machine tools;
for the production of lining and spars of cars, aircraft, helicopters;
for the manufacture of road signs and street signs.

D16T pipes are indispensable in the production of oil products. The production strings assembled by them are able to ensure uninterrupted operation of the well for 8 years.

Unlike steel tubes, duralumin tubes are plastic, easy to transport, durable and have a smooth surface. The only disadvantage of D16T pipes is the tendency to corrosion during prolonged heating, in an aggressive acidic or gaseous environment. However, this problem is successfully solved with the help of inorganic inhibitors, which create a thick oxide film on the surface of the pipes and reduce their sensitivity to intergranular destruction.