Aluminum alloys and their properties


Aluminium foil in different alloys

Aluminum is one of the most versatile materials, because depending on the alloy, the material can assume quite different properties. With the large number of different alloying possibilities and the resulting application areas it is sometimes difficult for the experts to keep an overview – especially since with the EN a four-digit number code has prevailed over the old German designations. A brief description of the most important aluminum alloys provides guidance on the selection of materials.

The European EN-AW standard: Shorter, but not clearer

Transport of aluminum rolls on pallets.

Jumbo aluminum rolls ready for shipping on pallets.

The old German nomenclature had its advantages, because due to the description of the alloy series, someone with knowledge of the industry immediately knew the amount of alloy elements.

The Euro norm (EN-AW), on the other hand, specifies only the main alloying component with the first digit. For all further information the data sheets have to be consulted.

The so-called “1-Group” is also called pure aluminum. This designation is somewhat misleading for strangers to the industry, because such pure aluminum has alloy additions of maximum one percent.

Even “pure aluminium” has additions of up to one percent.

In the following, the alloys are discussed in ascending order according to their EN-AW number. It should be noted, however, that alloys with numbers that are far apart nevertheless have quite similar characteristics, for example EN-AW 1200 and EN-AW 8079 or EN-AW 8011 and EN-AW 8111.

EN-AW 1050: Electrically conductive and decorative

The alloy EN-AW 1050, which according to the German alloy table is designated Al99.5, has a pure-aluminum content of 99.5%. Iron is with up to 0.5% the largest alloy in addition to the aluminum. In addition, copper, manganese, zinc, magnesium and other elements are added.

Aluminum EN-AW 1050 has very good electrical and thermal conductivity. It is easy to shape and weld. It is also ideal for brazing and soldering. It can be anodized for added protection and for decorative purposes.

These aesthetic properties make that type of aluminum a popular material for the car industry, which it uses for decorative elements. It is also widely used in lighting fixtures, lamellar of heat exchangers and in machinery in the chemical and food industry (apparatus engineering).

Do you use EN-AW 1050 for conviction or tradition?

The alloy EN-AW 1050 is “softer” than the below listed variants. EN-AW 1050 therefore has a relatively low tensile strength. This makes this alloy less suitable for some applications. Nevertheless, the EN-AW 1050 alloy is often used in these applications. This often has historical reasons because the respective specifications were written when the below listed alloys were not yet widely available.

It is often useful to switch to one of the following more modern alloys in order to use their advantageous properties.

EN-AW 1200: Excellent corrosion resistance

The alloy EN-AW 1200 has less aluminum than EN-AW 1050. 99% pure aluminum can be found in it. The old German designation is Al99.0: Main alloy components are iron, followed by silicon.

This alloy has many of the characteristics of EN-AW 1050: Good to shape, easy to weld, suitable for all soldering procedures, excellent for protective and decorative anodizing. EN-AW 1200 is used in the chemical and food industry as well as in heat exchangers. Particularly, this aluminum is excellent in corrosion resistance.

EN-AW 3003: Corrosion resistance and excellent molding ability

All aluminum alloys whose EN codes begin with the number 3 have manganese as their main alloying component. EN-AW 3003 is in the old alloy table with the abbreviation AlMnCu. The pure aluminum content is about 98%. Apart from manganese, copper is still found in EN-AW 3003.

Aluminum EN-AW 3003 cannot be heat-treated. Its strength is in the middle range.

Excellent features of this alloy are its excellent processing properties in the soft state: EN-AW 3003 can be welded, brazed and soft soldered as well as anodized for protection. Thanks to its good processing properties it is used in many areas: for office equipment, for kitchen appliances, for building construction, for decorative elements, for awnings and heat exchangers.

EN-AW 5754: Perfect for welding and seawater resistant

The natural hard aluminum EN-AW 5754, written according to the old alloy table AlMg3, has magnesium as the main additive. This applies to all alloys whose EN code number starts with the number 5.

EN-AW 5754 is particularly suitable for a wide variety of welded constructions. The anodizing properties of this material are also excellent.

The resistance to the long-term effect of sea water recommends this alloy for use in shipbuilding. For example, this aluminum is used in the production of technical enclosures. Thanks to the corrosion resistance and formability, EN-AW 5754 is used in plant construction for lining containers and tankers.

EN-AW 8011: A versatile, deep-drawn rolled product

Aluminum foils with many alloys.

Aluminum can be further processed in a variety of ways, For example by perforating, lacquering or embossing.

The remaining alloy – also called special alloys – is grouped under EN code 8.

EN-AW 8011 is one of the most common cold-rolled aluminum alloys. The old German spelling is AlFeSi (A). EN-AW 8011 thus entails, in addition to the main component of aluminum, mainly the alloying elements iron and silicon. EN-AW 8011 is non-toxic, hygienic, odorless, tasteless, corrosion-resistant and extremely resistant to deformation in the soft state.

Your lunch is probably packaged in a household foil made of alloy EN-AW 8011.

Therefore aluminium foil from the alloy EN-AW 8011 has a wide range of applications: it is used for the packing of kebab, pizza and fast food as so-called catering foil, and is also frequently used for the production of household foils from the supermarket.

In addition, EN-AW 8011 is thermo-formable. This is used in the production of tea lights, coffee capsules or wine bottle capsules.

The insulation material is EN-AW 8011e in heat exchangers. The material EN-AW 8011 is also used in multilayer and mobile pipe systems.

EN-AW 8079: Butter and coffee packaging and more

The alloy EN-AW 8079 offers many applications as well. According to the German table it is written as AlFe1Si. The order of the alloy components is therefore the same as for EN-AW 8011, and the alloy therefore has similar properties to EN-AW 8011: resistance to deformation and corrosion, hygienic and neutral surface, impermeability to environmental influences.

Tablet packs are often welded with blister film made of EN-AW 8079.

The EN-AW 8079 aluminum is an integral part of the packaging and food industry and is increasingly replacing the EN-AW 1200 alloy. It reliably protects coffee, butter, cheese and chocolate from light and environmental influences. The blister films used in the pharmaceutical industry are also frequently produced from EN-AW 8079.

In the technical field, EN-AW 8079 is used for cable wrapping, adhesive tapes and other insulation purposes.

EN-AW 8111: Durable and optimal for shaping

The elements iron and silicon are also mixed in the alloy EN-AW 8111 – AlFeSi (B). EN-AW 8111 has good mechanical durability while at the same time very good mold ability.

These properties make it ideal for the production of multi-jointed aluminum. In particular, it is used as a cover for the packaging of fresh food, but also for bottle neck films, for example, on the bottles of some beer brands.

 

Are you looking for aluminum foil? The choice of the alloy ultimately depends on the application.

We are happy to help!