Rolled aluminum: foil, sheets, plate

Алюминиевый прокат – aluminium foil и алюминиевый лист – small and large - approximately half of all aluminum products in the world.

Потребители алюминиевого проката

Самыми яркими представителями потребителей алюминиевого проката являются

Строительная отрасль в настоящее время является главным потребителем

  • листов для кровли и облицовки зданий.

The rapidly expanding market for the consumption of rolled aluminum is the transport engineering.

  • Aluminum sheets and
  • aluminum plates

used in aircraft, ships, high speed trains and military vehicles.

Increase in the proportion of aluminum

  • in car construction

becomes more and more important in the fight to save fuel and reduce harmful emissions into the atmosphere.

Finally, small, but a very important part of the foil is used in such specialized niches, as

  • electrical equipment,
  • heat exchangers and
  • lithographic plates.

What aluminum alloys are valued for

Aluminum alloys find such widespread use due to their combination of low weight, electrical and thermal conductivity, corrosion resistance, good machinability and a wide range of mechanical strength. Other important properties of aluminum alloys, as formability or weldability, very much depend on their chemical composition, as well as from the types of technological processes of their manufacture.

It is common engineering practice to select an aluminum alloy, which would be most suitable for the specific operating conditions of the product or even the development of a special alloy. The optimum microstructure of this alloy is achieved due to the chemical composition, as well as technologies for its thermal and thermomechanical treatment.

Rolling of aluminum alloys and their microstructure

Rolling is one of the most important technological processes for the processing of metal materials in their solid state.. It is a thermomechanical treatment, which has significant potential to control the microstructure of these metallic materials. Historically, rolling was at first just a process. Which was used to give the product the desired shape, for example, from ingot to sheet. Then rolling became an efficient and cost-effective process for controlling the microstructure of the metal and improving its properties.. An example would be cast structure modification and grain refining.

The microstructural variables for a given chemical composition of the alloy are:

  • grain size;
  • shape and orientation of grains;
  • subgrain sizes;
  • dislocation density;
  • size and shape of secondary phase particles and their volume distribution.

These parameters affect the mechanical strength and ductility of the material., as well as anisotropy of product properties. They depend on the chemical composition of the alloy and thermomechanical treatments, sometimes very difficult.

Aluminum alloys for rolling

Pure aluminum is lightweight - density 2,7 g / cm3, but very soft metal, which is only applicable in the electronics industry. Therefore, aluminum is usually alloyed with magnesium., manganese, silicon, zinc, copper and other elements. This makes it possible to increase the mechanical strength in the range from 50 to 650 MPa. Aluminum alloys, for which rolling, can belong to almost any series of wrought alloys - from the 1xxx series to the 8xxx series, except for the 4xxx series - mainly welding alloys. The 6xxx series combines mainly aluminum alloys for pressing (extrusion), but it also has alloys, from which sheets are rolled, for example, alloys 6061 (AD33) i 6082 (AD35).

The properties of each aluminum alloy depend on the metallurgical state of the material., which are denoted by the letters O, H and T with additional digits:

  • the letter O indicates the annealed state - soft and plastic;
  • letter H stands for cold-worked condition, usually after cold deformation;
  • the letter T stands for, that the material has received one or another heat treatment.

Generally, very schematically, we can say:

  • foil for packaging is made from alloys of the 1xxx and 8xxx series;
  • most sheets are made from alloys, which are hardened by auto-fretting - 3xxx (aluminum cans) and 5xxx (vehicle bodies);
  • most thick plates for aircraft construction are rolled from high-strength alloys – thermally hardened alloys of the 2xxx and 7xxx series.

Examples of rolled aluminum alloys (sheet 2-4 mm)

Aluminum alloy 1050A (AD0)

Chemical composition: 0,2 % silicon - 0,4 % gland.

1) Condition About:

  • yield point: 35 MPa;
  • tensile strength: 90 MPa;
  • elongation: 40 %.

2) State H14:

  • yield point: 115 MPa;
  • tensile strength: 125 MPa;
  • elongation: 20 %.

Aluminium alloy 2024 (D16)

Chemical composition: 3,8-4,9 % copper - 1,2-1,8 % manganese.

1) Condition About:

  • yield point: 140 MPa;
  • tensile strength: 220 MPa;
  • elongation: 13 %.

2) Condition T4:

  • yield point: 275 MPa;
  • tensile strength: 425 MPa;
  • elongation: 14 %.

3) Condition T8:

  • yield point: 400 MPa;
  • tensile strength: 460 MPa;
  • elongation: 5 %.

Aluminium alloy 3104 (D12)

Chemical composition: 0,8-1,4 % manganese - 0,8-1,3 % magnesium.

1) Condition About:

  • yield point: 60 MPa;
  • tensile strength: 155 MPa;
  • elongation: 15 %.

2) State H14:

  • yield point: 180 MPa;
  • tensile strength: 220 MPa;
  • elongation: 2 %.

3) State H18:

  • yield point: 230 MPa;
  • tensile strength: 260 MPa;
  • elongation: 1 %.

Aluminium alloy 5052 (AMg2.5)

Chemical composition: 2,2-2,8 % magnesium.

1) Condition About:

  • yield point: 65 MPa;
  • tensile strength: 170 MPa;
  • elongation: 15 %.

2) State H14:

  • yield point: 180 MPa;
  • tensile strength: 230 MPa;
  • elongation: 4 %.

3) State H18:

  • yield point: 240 MPa;
  • tensile strength: 270 MPa;
  • elongation: 2 %.

Aluminium alloy 5182 (AMg4.5)

Chemical composition: 4,0-5,0 % magnesium.
1) Condition About:

  • yield point: 110 MPa;
  • tensile strength: 255 MPa;
  • elongation: 12 %.

2) State H19:

  • yield point: 320 MPa;
  • tensile strength: 380 MPa;
  • elongation: 1 %.

Aluminium alloy 6082 (AD35)

Chemical composition: 0,7-1,3 % silicon - 0,6-1,2 % magnesium.

1) Condition About:

  • yield point: 85 MPa;
  • tensile strength: 150 MPa;
  • elongation: 16 %.

2) Condition T6:

  • yield point: 260 MPa;
  • tensile strength: 310 MPa;
  • elongation: 10 %.

Aluminium alloy 7075

Chemical composition: 5,1-6,1 % zinc - 2,1-2,9 % magnesium - 1,2-2,0 % copper.

1) Condition About:

  • yield point: 145 MPa;
  • tensile strength: 275 MPa;
  • elongation: 10 %.

2) Condition T6:

  • yield point: 470 MPa;
  • tensile strength: 540 MPa;
  • elongation: 7 %.

Источник: Handbook of Metallurgical Process Design, 2004