Wrought aluminum alloy according to GOST 4784-97

  • GOST 4784-97 specifies the chemical composition of wrought aluminum and aluminum alloys.

In addition to it, two more standards are related to the chemical composition of wrought alloys:

  • GOST 1131-76 for aluminum wrought alloy in ingots
  • GOST 11069-2001 for primary aluminum ingots.

Ingots of primary aluminum and wrought alloy ingot melted and prepared, suitable for the treatment of hot or cold deformation.

Stamps aluminum and aluminum alloy

Let us for convenience in the name aluminum alloys omit the word "brand", for example, "Aluminum alloy AD33", instead of "Aluminum Alloy stamps AD33 '. In my opinion, when naming alloys word "brand" seems entirely superfluous – quite enough words “alloy”.

To distinguish between the various embodiments use the term pure aluminum “aluminum brand”, for example, Aluminum grade AD00. In this case, it is useful, because alumina gradeI do not, by definition, aluminum alloys.

The standards CIS uses three types of symbols grades of aluminum and aluminum alloy: traditional haphazard alphanumeric and system numeric, as well as the international digital and chemical analogues of existing international. for instance, for alloy D1 it is: D1, 1110, AlCu4MgSi and 2017.

Designations aluminum alloys

Purely numerical designations were introduced in the late sixties of the last century and were conceived as part of an overall system of notation of all alloys of metals. The first digit 1 It was assigned to the aluminum alloys. The second digit must designate doping system. Then the first two digits, according to GOST 4784, denote aluminum alloys of different alloying systems, eg:

  • 10xx - technical aluminum;
  • 11xx - aluminum alloys of the Al-Cu-Mg system;
  • 12xx - alloys aluminum systems Al-Cu-Mn;
  • 13xx - alloys aluminum systems Al-Mg-Si;
  • 14xx - alloys of aluminum system Al-Mn;
  • 15xx - alloys of aluminum system Al-Mg;
  • 19xx - alloys of Al-Zn-Mg.

The last two digits determine the serial number of the alloy within a particular system, and, ostensibly, odd numbers should denote wrought alloys, and even - foundry. However, GOST 1583-93 for casting aluminum alloys any traces of numerical indicia is not visible.

Basically, This digital signage system never fully taken root and little used. Most alloys represent the "old", unsystematic alphanumeric designations, and standards, as GOST 4784, duplicate both variants. true, Some alloys have only one, digital signage, for example, alloy 1105, which is used for the manufacture of tapes and has neither the "old" designation, us “official” international counterpart.

Wrought alloys: GOST 4784-97

GOST 4784-97 It applies to aluminum and wrought aluminum alloys, intended for the manufacture of semi-finished products (tapes in rolls, sheets, plates, bands, bars, profiles, tire, pipe, wire, forgings and stampings) by hot or cold deformation, and slabs and ingots for further deformation processing.

Iron and silicon are inevitable constant impurities in aluminum and aluminum alloys. They form a ternary aluminum chemical compounds, that, special, if they are on the grain boundaries, reduce the ductility of aluminum. Therefore, the standard requires, to aluminum in the stamp, as well as the alloy AMtsS, the iron content was greater than silicon.

GOST 4784 It refers to aluminum wrought alloy doped with a total content of alloying elements and impurities more 1,0 %. The table below provides an overview alloys GOST 4784. For clarity omitted specific welding alloys and variants alloy wire for cold heading.

 

spalvy-aljuminievye- gost-4784-97

soft alloys

Aluminum grades (series 1xxx)

The content of impurities (or alloying elements) is not more than 1,00 %.

Aluminum alloys Al-Mn (3xxx series)

Non-thermally hardened alloys .

(Note, that we use the word “neuprochnyaemye” writing particles with conjoint “not”. This word in this case, – adjective, instead of communion. Adjectives are written with a particle “not” slit, but Communion – apart. This is what we remember from school. 🙂 )

Interesting, This system has a connection formally Al6Mg variable solubility and its alloys should be heat-hardening. However, is, in the presence of inevitable impurities - iron - instead of the soluble phase formed insoluble aluminum compound Al6(Mn, Fe). Manganese, Unlike other alloying elements, does not deteriorate, and improves the corrosion resistance of the alloy. Therefore, these alloys are superior to aluminum and technical strength, and corrosion resistance.

There are not so many alloys of this system in the standard:

  • MM,
  • AMC,
  • AMCs
  • D12.

All of them are used, primarily, in the form of sheets and strips of cold-worked in various states.

Alloy designations of this system are an example of complete haphazard (sorry for the pun!) Alloy designations in our standards. Similar to an IQ test: “D1, D16, D18, D19 - duralumin. Is alloy D12 also duralumin?” Correct answer – not.

Moderately strong aluminum alloys

Aluminum alloys Al-Mg (5xxx series)

Thermally not reinforcing.

Magnesium in an amount up to 6 % hardening gives solid solution alloy and a high strain hardening efficiency. Therefore 5xxx series alloys have a relatively high strength properties. These alloys commonly have good corrosion resistance, particularly corrosion resistance in sea water and marine atmosphere, and therefore are widely used in shipbuilding, mainly in the form of sheets. Of these alloys are manufactured pressed housing parts and vehicle chassis due to the good combinations of strength and formability.

Aluminum alloys Al-Mg-Si (6xxx series)

These alloys are sometimes (only in our country) called "aviales".

Hardening phase compound is Mg2Si.

Aluminum alloy AD31 - full analogue of "American" Alloy 6063 and, partially, "European" alloy 6060. The ratio of the average content of silicon and magnesium in it is close to the stoichiometric ratio 1: 1.73 for Mg compound2Si.

  • AD31 (6060/6063) – the most popular industrial aluminum alloy. It is widely used for the manufacture of aluminum profiles for building envelopes (windows, doors, facades) and others, usually, no load-bearing structures.
  • Aluminum alloy AD33 - analogue alloy 6061. Greater magnesium and silicon content, than AD31 (silicon in excess), and additive copper. more durable, than AD31. Applicable bearing building constructions.
  • Aluminum alloy AD35 - analogue alloy 6082. Compared with the alloy AD33 magnesium almost as many, as in the alloy AD33, silicon and a half times longer, and further to 1 % manganese. Therefore, alloy AD35 more durable, than AD33. Applicable bearing building constructions.

Solid aluminum alloys

series 2xxx – Aluminum alloys Al-Cu-Mg and Al-Cu-Mn

Thermally hardenable alloys.

The so-called Duralumin or duralumin. Depending on the content of copper and magnesium, and the ratio of their concentrations, various hardening phases can form in them: double or triple compounds of aluminum with copper, magnesium and manganese.

  • Aluminum alloy D1 - "classic", duralumin with normal hardening phase CuAl2.
  • Alloy D16 - more durable, the so-called "superdyuralyumin", in comparison with D1 contains an increased amount of magnesium (on average 1,5 %). Therefore, the main strengthening phase it is already ternary phase CuMgAl2, which gives higher strength.

A letter does not necessarily mean “dyuralyuminii, duralumin”, as it may seem. There is an aluminum-manganese alloy D12 – soft and ductile.

The strength of duralumin depends on the type of semi-finished product: there is more in the rods, sheets - less. The tensile strength of the normal sheet reaches D1 410 MPa, and the sheet F16 - 440 MPa.

  • Aluminum alloy D18 is specifically designed for rivets, it contains a reduced amount of copper and magnesium and, therefore, has substantially lower strength, but higher ductility, than, let us say, duralumin D1.
  • B65 aluminum alloy for the rivets, which operate at a temperature no higher than 100 ° C.
  • Aluminum alloys AK (AK4, AK6 and AK8) - close "relatives" of duralumin - intended for forgings and stampings. The letter K just means: Forging.

series 7hhh – Aluminum alloys are Al-Zn-Cu-Mg

Thermally hardenable alloys.

They include the most durable aluminum alloy – alloy V95. Known more durable aluminum alloy – B96, but it is not included in the Standard 4784-97.

  • Aluminum alloy has a zinc content of V95 by 5 to 7 %, magnesium from 1,8 to 2,8 % and copper from 1,4 to 2 % at the limit of green strength 600 MPa. B96 alloy has strength under 700 MPa when the content of zinc 8 to 9 % and increased content of magnesium and copper.
  • Aluminum alloys 1915 and 1925 are convenient, that are, so to speak, samozakalivayushtimisya. Their strength depends little on the type of quenching medium (water, air). Therefore, during compression of these profiles with flange thickness up to 10 mm are cooled in air. Aging is carried out both at room, and at elevated temperatures.

Sources:

GOST 4784-97 Aluminum and Wrought Aluminum Alloys
Gulyaev AP. metal science. M: Metallurgy, 1986.