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Drawn Tubing
Drawn tubing usually produces product that meets more stringent specifications than extruded product of the same alloy and size. Cold drawing (a type of drawn tubing process) is where extruded stock is drawn through a die or a series of dies in order to reduce the outside dimension of the tube.

Electrolyte
Electrolyte in a cell is mainly liquid cryolite, aluminum fluoride and calcium fluoride. It is used to dissolve alumina.

Electrolytic reduction process
The electrolytic reduction process was invented by Charles Martin Hall and Paul-Louis Toussaint Héroult in 1886. It is a chemical process in which aluminum is extracted from alumina by passing electric current through a bath of electrolyte at temperatures of around 960°C. This bath of molten cryolite is contained in a carbon-lined steel shell, which acts as the cathode, with alumina being dissolved continuously in the solution. Carbon anodes are dipped into the bath and, by means of electrical energy, the alumina is broken down into aluminum and oxygen. The molten aluminum collects on the cathode bottom from where it is siphoned off.

Electrolysis
Splitting chemical compounds with the help of direct current.

Extrusion ingot
Cast metal used by the extrusion industry. Also called billet when cut to length.

Extrusion billets
Aluminum ingots in cylindrical form which are used to manufacture extruded and drawn products.

Extrusion process
The extrusion process involved pressing a preheated aluminum billet under high pressure through a die the opening of which corresponds to the cross-section of the extrusion. The number of tons of pressure exerted determines how large an extrusion can be. The hardness of the alloy used in the billet determines how fast the extrusion can pass through the press. A completed extrusion is cut off at the die, the cooled and aged. Depending on the billet size and die opening, continuous extrusions can be up to 200 feet long.

Fabrication process
The fabrication process involves further work and processing of extruded aluminum after it comes out of the extrusion press and is properly cooled and aged. Fabrication services can include joining (welding, bonding, riveting), forming (bending, stretching), and machining (cutting, drilling, mitering, notching).

Finishing process
After extrusion and fabrication, finishing of the final product may include surface treatments (painting, anodizing, etc), custom packaging (labeling, binding, etc) and other special operations.

Fluorides
Salts of fluoride. Fluoride is the everyday term for aluminum fluoride and hydrogen fluoride.

Foil
Produced by rolling, aluminum foil is less then 0.02mm thick. It is impervious to gas and light, it is soft and flexible and is highly suitable for the packaging of food and medicines. Aluminum foil is used plain, e.g. for household foil, or converted, e.g. printed, coated, laminated or embossed.

High-purity aluminum
Aluminum with a degree of purity of minimum 99.98 per cent. High-purity aluminum is the starting material for products used in the electrical engineering, electronics and optical industries. High-purity aluminum displays high electrical and heat conductivity. High-purity aluminum is produced by means of different processes, e.g. three-layer electrolysis or the zone refining process, depending on the degree of purity required.

Homogenizing
Controlled heating of extrusion ingot.

Lithography
Surface treatment of aluminum plates for planographic (flat) printing in which the printing ink is taken up by the different surface properties.

LME price
The LME price is the market price at which aluminum is currently being traded.