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Aluminum "6061"


Aluminum Spav 6061 - its composition, applications, analogues and excellent designations in industrialized countries.

Pure aluminum is a fairly soft metal - almost three times softer than copper, even relatively thick aluminum profiles are easy to bend. But when aluminum forms alloys, its hardness increases tenfold.

Aluminum 6061 according to ISO 209-1 - aluminum-magnesium-silicon alloy.


Al - 95.8-98.6%. Aluminum is an element of the main subgroup of the third group of the third period of the periodic table of elements with atomic number 13. It belongs to the group of light metals.
Mg - 0.8-1.2%. Magnesium is the main additive in aluminum alloys of the six-thousand series, greatly increases strength without reducing ductility - with each percent increase in concentration the ultimate strength is increased by 30 MPa, the yield strength by 20. Also increases weldability and corrosion resistance, but with an increase in concentration above 3% the structure of the alloy becomes less stable, and with a magnesium content of more than 6% corrosion resistance begins to decrease.
Si - 0.4-0.8%. Silicon is generally the most used additive in foundry alloys, and it is used as an alloying element in aluminum alloys.  At concentrations of 0.5-4% it reduces the tendency to cracking. In combination with magnesium it makes the alloy thermo-compaction possible.
Fe - up to 0.7%. Iron contributes to the high stability and heredity of the cast structure of aluminum and its alloys, reduces sticking to the walls when cast in molds, however, reduces the electrical conductivity and chemical resistance.
Cu - 0.15-0.4%. Copper is used as an alloying element and significantly increases strength when combined with magnesium, zinc and silicon.
Cr - 0.04-0.35%. Chromium is introduced into alloys to neutralize the negative effects of iron, as well as to improve the strength characteristics of the material and welded joints.
Zn - up to 0.25% - Zinc is used as an alloying element together with copper and magnesium to increase strength.
Ti - Up to 0.15%. Titanium is used to refine the grain of the cast metal and also greatly reduces the tendency to crack.
Mn - up to 0.15%. Manganese is used as an alloying element - the recrystallization temperature increases, the structure of cold-deformed material is refined, the strength properties at room temperature increase, and the heat resistance increases significantly.
So, we have a fairly strong alloy with good ductility, heat sealing capability, high corrosion resistance and quite normal weldability. These characteristics allow the use of aluminum 6061 in the widest and most diverse range.


General use - for parts of medium strength and high corrosion resistance operating in the temperature range from -70°C to +50°C, in a humid atmosphere and seawater.

More specific applications.

In the U.S. automotive industry, body struts are made from pressed semi-finished 6061 alloys.
A very common application is bike frames, including BMX.
In aviation, alloy 6061 is used in low-loaded parts, as well as in hydraulic, oil and fuel systems.
In U.S. rail transport, alloy 6061 and other aluminum alloys are used to make rolling stock with optimal strength characteristics and high corrosion resistance of welded elements.
The construction industry uses more aluminum for related building structures than any other industry. The alloy is used in complex-shaped laminated and riveted structures, as well as in structures that require a high yield strength, and for complex-shaped pressed products (hollow sections).
The US oil industry uses 6061 alloy tubing for offshore drilling platforms.
In the chemical industry this alloy is used for making containers, tanks and other equipment for storing acetic acid, high-molecular fatty acids, alcohols, as well as for the manufacture of containers for storing ammonium nitrate.
Metal matrix composites (MMC) with 6061 alloy were successfully used for manufacture of the Space Shuttle body (as a body kit).

The 3.6 m long telescopic beam of the Hubble space telescope antenna was made on the basis of MMK from diffusion bonded layers of graphite fibers with this alloy.