CHARACTER Aluminium, a metallic element which comes from the ore bauxite, is one of about 100 basic elements out of which the earth is built. Bauxite is named after Les Baux, France, where it was first discovered in 1821. Aluminium is a light metal which can be given tremendous strength by alloying. It conducts heat and electricity, reflects light and radiant energy and resists corrosion. It is also non-magnetic, non-toxic, and can be formed by all known metal working processes. Because of these advantages it has thousands of uses. The following table outlines some of its features and uses. - Characteristics Available forms Typical uses 1200 'Commercially pure' aluminium. Very ductile in extruded condition. Excellent resistance to corrosion. Simple shapes. Mouldings, lightly stressed and decorative assemblies in architecture and transport, equipment for chemical, food and brewing industries; heat exchangers. 6063 Suitable for intricate extruded sections of medium strength. Forms well in T4 temper. High corrosion resistance. Good surface finish. Excellent finishing characteristics especially anodising. All shapes. Tubing, rod. Architectural members such as glazing bars and window frames. Windscreen sections. Road transport trim. 6005 General purpose structural alloy. Good mechanical properties, corrosion resistance and weldability. Structural shapes. Rod, bar and tubing. Structural applications of all kinds. Road and rail transport vehicles, cranes, bridges, roof trusses etc. Drive screws, bolts and nuts. 6060 Special purpose structural alloy. Good surface finish and corrosion resistance. Good formability in T4 temper. Good weldability. Responds well to surface finishing, especially anodising. Structural shapes of all kinds. Rod, bar and tubing. Offered in the T5 temper with the same mechanical properties as 6351 T6. Structural applications where surface finish is important or where thin, intricate shapes are involved. Yacht masts, road transport sections, e.g. Plankflor. Ladder sections. 6082 The recommended alloy for structural purposes with good strength and general corrosion resistance. Good weldability. Structural shapes. Rod, bar, tubing. Vehicles, bridges, cranes, roof trusses and all general structural applications. 2011 Free machining alloy of medium strength giving fragmented chips. Not suitable for anodising. Rod and bar. Automatic lathe products.   ALLOYS Aluminium's, range of properties can be found in an impressive array of commercially available alloys. The composition and logic of those alloys are regulated by an internationally agreed classifications system or nomenclature for wrought alloys and by various domestic nomenclature schemes for the casting of alloys. The wrought scheme is as follows. Each registered alloy is described by a four digit number, with a further letter and number indicating the temper, or condition of the alloy, for example 6082-T6 is a medium strength grade based on the aluminium-magnesium-silicon family, in the fully heat-treated condition. The classification provides for: 1XXX Aluminium at 99% minimum purity 2XXX Aluminium-Copper alloys 3XXX Aluminium-Maganese alloys 4XXX Aluminium-Silicon alloys 5XXX Aluminium-Magnesium alloys 6XXX Aluminium-Magnesium-Silicon alloys 7XXX Aluminium-Zinc-Magnesium alloys 8XXX Miscllaneous alloys e.g. Aluminium-Lithium alloys Alloys fall into two main groups. The work-hardening alloys, where strength is achieved by the amount of "cold work" applied to the alloy for example, by rolling, and heat-treated or precipitation hardening alloys, where the strength and properties are achieved by heat treatment of varying complexity