Extrusion of aluminum alloys in the automotive industry

In the production of passenger cars, two types of wrought aluminum alloys are used:

  • extrusion alloys - for profiles and
  • rolled alloys - for sheets.

The following summarizes the basic aluminum extrusion alloys, which are used in the automotive industry.

The chemical composition and the use of alloys cm. Aluminum in the car: extrusion alloys

mark 1050

aluminum Brand 1050 series of technical aluminum 1xxx. It has low strength properties, but a very high capacity for forming, that is, the ability to withstand large plastic deformation under pressure treatment - extrusion, hot and cold rolling, and punching and other such operations.

aluminum Brand 1050 contains no special alloying elements - are present therein as inevitable impurities with a minimum content of aluminum 99,50 %.

Nominal chemical composition: Al99.50.

For rolled products, typical material states are:

  • hard-worked to various degrees (Н1х);
  • work-hardened and partially annealed to various degrees of residual work-hardening (Н2х);
  • annealed (O).

For pressed products, the typical material state is H112: hot pressing and stretching..

aluminum Brand 1050 used both in pressed (extruded) products - profiles, bars and tubes, and in rolled products - sheets and foils.

Alloy 3003

Alloy 3003 for extrusion, hot and cold rolling, as well as drawing. It has strength properties from low to medium, and very good moldability metal forming methods. The main alloying element is manganese, which among other functions provides good control of recrystallization and grain size. Another alloying element is copper, which improves the strength properties.

Nominal chemical composition: Al-1.2Mn-0.12Cu.

For extrusion products typical state material is H112, i.e, hot pressing and stretching the minor edits.

For typical alloy rolled product states 3003 are:

  • hard-worked to various degrees (Н1х);
  • work-hardened and partially annealed with varying degrees of residual work-hardening (Н2х);
  • annealed (O);
  • after hot pressing and slight tensile straightening (H112).

alloy 6005A

Thermally hardenable extrusion alloy of series 6xxx middle-mechanical properties. Magnesium and silicon are principal alloying elements, manganese and chromium - special additives.

Nominal chemical composition: Al-0.7Si-0.6Mg-MnCr

The strengthening component is the intermetallic compound Mg2Si. At the nominal chemical composition of the alloy 6005A has a content of magnesium silicide, Mg2Si around 0,9 %, a 0,4 % silicon is in excess, ie non magnesium. Manganese and chromium suppress recrystallization to control the shape and grain size.

The typical material condition for alloy 6005A is T6:

  • heating profiles when 530 ºS;
  • water hardening;
  • artificial aging at 175 ° C within 8 hours.

Another popular condition is T4: natural aging with 20 ° C within 4 days after the same heating and quenching, for the T6 condition.

Alloy 6008

Thermally hardenable extrusion alloy of series 6xxx middle-mechanical properties. The main alloying elements - magnesium and silicon without special additives.

Nominal chemical composition: Al-0.7Si-0.6Mg-Mn.

The typical material condition is T5:

  • hardening from the pressing temperature (about 520 ºS) i
  • artificial aging at 175 ° C within 8 hours.

Alloy 6014

Thermally hardenable alloy extrusion of the 6xxx series. The level of mechanical properties - low to medium. The main alloying elements - magnesium and silicon, special supplement – manganese.

Nominal chemical composition: Al-0.45Si-0.6Mg-Mn.

The typical material condition is T6:

  • hardening temperature 530 oC and
  • artificial aging at 175 ° C within 8 hours.

Alloy 6060

Thermally hardenable alloy extrusion of the 6xxx series. The level of mechanical properties - Low. The main alloying elements - magnesium and silicon, No special additives.

Nominal chemical composition: Al-0.5Si-0.4Mg.

The reinforcing component heat treatment - the intermetallic compound Mg2Si. At the nominal chemical composition of the alloy 6060 It has a content of magnesium silicide, Mg2Si around 0,7 %, a 0,2 % silicon is in excess. All other elements are considered impurities.

Absence of additives sometimes creates problems with grain sizes during heating for quenching and tempering.

The typical material condition is T5:

  • hardening from the pressing temperature (about 520 ºS) i
  • artificial aging at 175 ° C within 8 hours.

Alloy 6061

Thermally hardenable alloy extrusion of the 6xxx series. The level of mechanical properties - high. The main alloying elements - magnesium and silicon, special additive - chrome. In the automotive industry it applies only in the form of extrusion products - extruded profiles.

Nominal chemical composition: Al-1.0Mg-0.6Si-0.30Cu-0.20Cr.

Hardening heat treatment components - the intermetallic compound Mg2If и AlCuMg, which are formed during aging. At the nominal chemical composition of the alloy 6061 It has a maximum content of magnesium silicide, Mg2Si around 1,3 %. chromium additives inhibit recrystallization and grain growth.

The typical material condition is T6:

  • quenching with water of a temperature of about 535 oC and
  • artificial aging at 175 ° C within 8 hours.

Natural aging (T4) occurs at room temperature for 8 day.

Alloy 6063

Thermally hardenable alloy extrusion of the 6xxx series. The level of mechanical properties - low to medium. The main alloying elements - magnesium and silicon, special additives - no.

Nominal chemical composition: Al-0.7Mg-0.4Si.

The reinforcing component heat treatment - the intermetallic compound Mg2Si. At nominal - stoichiometric – the chemical composition of the alloy 6061 It has a content of magnesium silicide, Mg2Si around 1,0 % without excessive silicon. The absence of additives sometimes creates problems with the grain.

The typical material condition is T5:

  • water hardening from the pressing temperature (about 520 ºS) i
  • artificial aging at 175 ° C within 8 hours.

Alloy 6082

Thermally hardenable alloy extrusion of the 6xxx series. The level of mechanical properties - high. The main alloying elements - magnesium and silicon, special additive - manganese.

Nominal chemical composition: Al-1Si-0.9Mg-0.7Mn.

The reinforcing component heat treatment - the intermetallic compound Mg2Si. At the nominal chemical composition of the alloy 6082 It has a content of magnesium silicide, Mg2Si around 1,4 % c excess of silicon in an amount 0,5 %. Manganese helps control the shape and size of the grains during heat treatment.

The typical material condition is T6:

  • quenching water temperature 540 oC and
  • artificial aging at 175 ° C within 8 hours.

Natural aging (T4) – at room temperature for 8 day.

Alloy 6106

Thermally hardenable alloy extrusion of the 6xxx series. The level of mechanical properties - low to medium. The main alloying elements - magnesium and silicon, special additive - manganese.

Nominal chemical composition: Al-0.45Si-0.6Mg-Mn.

Heat treatment - the same as for the 6005A alloy.

This alloy was developed relatively recently for the manufacture of complex shapes with small thickness. Moreover, alloy 6106 It possesses a good combination of mechanical properties, high surface quality and outstanding ability to plastic deformation.

Alloy 7003

Typical thermally hardenable extrusion alloy of the 7xxx series. The level of mechanical properties - medium. The main alloying elements - zinc and magnesium, special additive - zirconium.

Nominal chemical composition: Al-6Zn-0.8Mg-Zr.

The reinforcing component - intermetallic compound MgZn2. Zirconium is used to control the process of recrystallization.

Typical conditions are material T53 and T63. T53 status includes:

  • hardening from the pressing temperature (about 450 ºS);
  • natural aging at a temperature no higher than 40 ° C within 3-4 days;
  • two-stage artificial aging (first stage - 100 ° C within 8 hours and the second stage - 150 ° C within 15 hours).

To achieve the T63 condition profiles quenched with water after heating at 440 ° C, and then the natural and artificial aging of similar T53.

Source: Aluminum @ Cars. Design, Technology, Innovation; Edimet, 2005