Aluminium

Verbrauchereigenschaften von Aluminium

Die Verbrauchereigenschaften von Aluminium und seinen Legierungen ermöglichen eine breite Anwendung von Aluminiumprodukten in vielen Bereichen der menschlichen Tätigkeit.

Korrosionsbeständigkeit

There is always a thin natural oxide film on the aluminum surface. This film is firmlyattachedto the base metal. Deswegen, it provides most aluminum alloys with a significant Korrosionsbeständigkeit in many atmospheric and chemical environments. Especially distinguished in this series alloys 1xxx, 3xxx, 5xxx and 6xxx. It is an important consumer properties of aluminium and aluminium alloys.

Feige. 1 – Der Oberflächenoxidfilm ist eine natürliche Quelle des Korrosionsschutzes [TALAT 1252] [1]

Thermal conductivity

  • Aluminum and aluminum alloys are good conductors of heat. The thermal conductivity of aluminum alloy is more than four times higher, than that of carbon steels.
  • They begin to melt at a much lower temperature, than steel.
  • The melting point of pure aluminum handelt von 660 ° C.
  • Aluminiumlegierungen, depending on the degree of alloying, begin to melt at lower temperatures, Zum Beispiel, bei 515 ° C for alloy 2017.

Feige. 2 – Wärmeleitfähigkeit von Aluminium im Vergleich zu anderen Metallen [TALAT 1501] [1]


Feige. 3 – Erstarrung von reinem Aluminium [TALAT 1201] [1]

Сonductivity

Pure aluminum and some of its alloys have very high electrical conductivity (low electrical resistance). This is an important consumer property of aluminium wires. Among the metals, which are used as electricity conductors, in this they are second only to copper. Gleichzeitig, on high-voltage power lines, it is usually used precisely aluminum wires. They have a larger cross-section, than the equivalent copper wire, however and half the weight. This allows, insbesondere, less put the support and reduce their height.

Feige. 4 – Elektrische Eigenschaften von Aluminium [TALAT 1501] [1]

Strength to weight ratio

High strength/weight ratio (relatively high strength at low density) determines the high efficiency of aluminum alloys as structural materials. Deswegen, this opens up wide opportunities for replacing heavier metals with aluminum without losing the bearing capacity of the product or part. This consumer property of aluminum alloys, combined with good corrosion resistance, provides them with a wide range of consumer applications., Zum Beispiel, in transport engineering (aircraft, cars, passenger cars).


Feige. 5 – Volumen pro Gewichtseinheit [TALAT 1501] [1]

Aluminum at low temperatures

Aluminiumlegierungen, especially alloys series 3xxx, 5xxx and 6xxx ideally suited for operation at low temperatures. Numerous data confirm, their ductility and toughness, as well as strength, above at low temperatures, down to absolute zero, than atroom” Temperatur. This is a very important consumer property of aluminium alloys for aerocosmic industry.

Feige. 6 – Zugeigenschaften von 6061 Legierung wärmebehandelt, Künstlich gealtert [TALAT 1501] [1]

Тechnological processing

Aluminum alloys are easily processed by most known metal forming technologies and are particularly easy to extrude.. Extrusion is the process of forcing heated metal through a die., forming profiles with complex cross-sections. This consumer property of aluminum alloys makes it possible to produce from them extruded profiles with a virtually unlimited variety of cross-sectional shapes. This allows you to have the metal in those areas and thus, to ensure that the profile of the maximum load-bearing capacity under the influence of the given loads.

Feige. 7 – Eingerüstiges Warmwalzwerk [TALAT 1301] [1]

Feige. 8 – Vorwärts- oder Direktextrusion [TALAT 1302] [1]

Aluminium joint methods

Details of aluminum alloy are joined by a large number of ways, einschließlich, quarrel, rations, riveting, screw connections. Schweißen von Aluminium may seem difficult for those, who has experience only with steels and try to move it to the aluminum. Welding aluminum alloys consider pretty easy, when used proven techniques such, like consumable arc welding (ME) and tungsten non-consumable electrode (WIG) in an inert gas environment.


Feige. 9 – Verbindungssysteme für dünnwandige Aluminiumbauteile [TALAT 4101] [1]

Reflectivity and emissivity

Emissivity – it’s lightness, with which the substance radiates its own thermal energy. It is closely related to reflectivity: the best reflective surface is the worst emitter., und, conversely, the worst reflective surface is the best emitter.

Ordinary aluminum reflects about 75% light falling on it and 90% thermal radiation. Jedoch, the emissivity of the same aluminum is low. He makes up <10% from the emissivity of a black body at the same temperature and in the same environment. The combined properties of high reflectivity and low emissivity lead to the use of aluminum foil as a reflective insulating medium [1].

Feige. 10 – Reflektivität und Emissionsgrad von Aluminium mit verschiedenen Oberflächenbehandlungen [1501] [1]


Feige. 11 – Vergleich der Reflektivität verschiedener Metalle [1501] [1]

Aluminum recycling

An important characteristic of the alloys is aluminum, what their Istworn cycle almost completely enclosed They are easy to reuse – retsiklingu. Unlike other construction materials, they are processed almost the same high-quality products.


Feige. 12 – Aluminiumproduktion aus Schrottrecycling [TALAT 1100] [1]

Feige. 13 – Energiebedarf für Primär- und Recyclingaluminium.
Energieeinsparung von bis zu 95% werden pro Tonne aus Schrott hergestelltem Aluminium im Vergleich zu Primäraluminium erreicht [2].

Quellen:

  1. TALAT-Vorlesungen
  2. Aluminiumrecycling in Europa Der Weg zu hochwertigen Produkten – Geschäftsbereich EAA/OEA-Recycling