Mining raw materials
Bauxite is a raw material which contains largely Al203 aluminum oxide. About 8,5% of the earths surface is covered with bauxite, herewith aluminum, oxygen and silicon are the most common elements on earth.
Within the process of aluminum production bauxite will be joint with warm caustic soda, the caustic soda reacts with the existing aluminum oxide in bauxite and forms natrium hydroxyde. The remaining components of bauxite will settle and filtered to get a pure hydroxyde.
The natrium aluminum hydroxyde will subsequently be cooled down which results in crystallizing of aluminum hydroxyde and a remaining of caustic soda, the aluminum hydroxyde will be heated (calcined) with as result the arise of aluminum oxyde called alumina.
The aluminum oxyde powder (alumina) will be joint with cryolite and heated at a temperature of 1000 degrees celcius direct current (DC) will be fed thru the fluid.
Meanwhile the alumina is solved in the cryolite and will be split via electrolysis with as consequence a release of oxygen and liquid aluminum this will be carried away and transferred to the foundry.
At the foundry liquid aluminum will be purified and eventually mixed with other alloys (depending on the needed quality criteria).
Out of this aluminum mixture roll slices and press bars will be made, the roll slices and press bars are the base for the most aluminum products.
From 4000 Kg bauxite approximately 1000 Kg aluminum will be subtracted.
Compri aluminium delivers several grades of aluminum, these aluminums do have several elements which have common grounds.
This quality aluminum is unalloyed and non thermical hardenable.
Increasing the strenght of aluminum is only possible by means of cold deformation which as cosequence has a decrease in stretch and deformability.
The corrosion resistance of aluminum is under normal condition excellent and at request it can be upgraded by means of technical anodizing. If this aloy is in soft glowing condition it is perfectly deformable.
Pure aluminum and alloys which do not contain copper behave excellent in several surroundings, therefor the copper free alloys are used as a standard within the construction branch.
In several other industries aluminum is regularly used and therefor a material which is all around us and a base for many products.
One of the most important properties of aluminum alloy is corrosion resistance, several different alloys are used within several different surroundings. To increase corrosion resistance a choice of surface treatment can be made.
Aluminum can be treated in many ways, within the construction industrie two types of surface treatment are used, anodizing and muffling (powder coating).
Durring the chemical process of anodizing the natural existing oxides in alloys wil be strenghtened.
Durring powder coating the aluminum will be first chemically cleaned and defatted, the next step in the process is to statically charge the aluminum.
When static aluminum is charged it can be sprayed with a negative charged powder (the actual paint) which results in a strong bond of the powder on the aluminum.
Thereafter the aluminum will be placed in a oven where the powder will be hardened towards a very strong durable lacquer layer.
Aluminum is a very strong product which thru its positive properties is well to deform under the right circumstances, these deformation properties give the aluminum a possibility to be extruded in almost every profile or tube with several diameters.
Aluminum melts at a point of 660 ?C, the different aloys in aluminun have no melting point but melt according a melting scale which is different per alloy.