Aluminium
Long-lasting connections – outstanding visual appearance
Aluminium is a lightweight and at the same time solid material that is used wherever stable components must not weigh very much. The material is used in alloys in aerospace, as well as in the construction of railway vehicle, motor vehicles and ships. TIG, plasma, MIG or even laser welding methods are used, depending on the specification and the thickness of the workpiece.
Light, solid, malleable
Aluminium has high specific strength. In comparison with steel, components made of aluminium are half as heavy with the same strength. Strengths are achieved in alloys with magnesium, silicon and other metals that are only slightly lower than those of steel. Thanks to its oxide layer, aluminium is extremely weatherproof and noncorroding. Pure aluminium and all hardened aluminium alloys are welded very easily. However, it should be noted that aluminium is easily deformed because of its high thermal conductivity. In addition, it has a relatively low melting temperature of about 660°C. In contrast, the melting temperature of the oxide layer on the aluminium is over 2000°C, and for this reason it is very important to remove the oxide layer before welding to achieve optimal weld strength and quality.
MIG and TIG welding
Only inert shield gases, both argon and also argon-helium mixtures, are used when welding aluminium. Thin aluminium sheets with a thickness from 0.5 mm can be easily welded with the TIG and plasma methods, and thicker sheets are welded advantageously using the plasma tap hole welding method. Weld quality and visual appearance are usually very good, and suitable filler metals can be found easily for heavy alloys as well. It is important to weld using alternating current, in order to break open the oxide skin.