Aluminium is the second most plentiful metallic element on earth. In its pure or alloyed form, aluminium is also the second most widely used metallic material after steels. Among the most striking characteristics of aluminium is its versatility. The range of physical and mechanical properties that can be developed, from refined high-purity aluminium to the most complex alloys, is remarkable. More than three hundred alloy compositions are commonly recognised, and many additional variations have been developed.
The most important properties of aluminium and its alloys are:
- low density (2700 kg/m3);
- good mechanical properties, with some alloys exceeding structural steel in strength;
- good workability permitting most varied shapes to be produced;
- good castability with a variety of casting techniques: sand, mould, die-casting;
- excellent machinability;
- ease of joining using all commonly applied techniques;
- comparatively high corrosion resistance thanks to the spontaneous formation of a strongly-adherent passivating surface film in air;
- different surface treatments are applicable, such as anodisation;
- high electrical and thermal conductivity, especially of unalloyed aluminium;
- good optical properties depending on the degree of purity;
- low absorption cross section for thermal neutrons;
- non-combustible, not causing sparking;
- nontoxic, being routinely used in containers for foods and beverages;
- excellent recycling.
Many of these properties are nevertheless strongly dependant on the concentration of alloying additions and impurities (the main alloying elements of aluminium materials are copper, silicon, magnesium and zinc – more information on this subject can be found here).
The uses of aluminium and its alloys are virtually limitless, covering the fields of transport; electrical, structural, civil and general engineering; household items; packaging in the chemical and food industries and many more:
- Applications in transport include cladding and door sections of commercial vehicles, prepainted sheet for caravans, the superstructure of ships and hovercraft and a variety of components in aircraft.
- Electrical engineering uses include large and small cables, foil, and strip windings for coils and transformers.
- Structural and civil engineering uses include roofing and structural applications, door and window frames and a variety of decorative items.
- General engineering uses include watches, photographic equipment, machinery for textiles, printing and components for machine tools.
- Household items using aluminium include electrical appliances, pans and furniture; and packaging uses foil for food, drink, tobacco and chemicals.
At CNC Proto we specialise in the machining of non-ferrous metals, mostly 6000 and 7000 series aluminium alloys, and engineering plastics. You can see a list of our most used alloys in our Services page. If your parts require a specific aluminium alloy other than the ones listed, feel free to let us know on our Quote request form!
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