Generative production & modification of Al components Laser powder cladding of aluminium alloys
As a light metal, aluminium is becoming increasingly important in today’s world. Due to a general scarcity of resources, lightweight, high-strength and isotropic materials are playing an ever important role. As a result, aluminium has become an indispensable ingredient in various industries, such as aerospace, the automobile industry and mechanical engineering.
The element’s differences to steel, such as its lower melting point, higher reflectance, higher thermal conductivity and greater expansion coefficient, and also the large delta between the melting points of the oxidation layer and aluminium itself, pose certain challenges to the welding process. The strict quality requirements in these industries can only be met by high-precision, high-energy and automated processes, such as laser powder cladding.
The problem with laser powder cladding of aluminium
The great affinity of aluminium to oxygen results in the creation of a thin oxide layer on the surface. The melting point of this oxide layer is over 1900 °C, which is more than triple that of aluminium itself. This oxide layer has an immensely disruptive effect on the welding process and results in a lack of fusion. Furthermore, hydrogen is emitted during the solidification process for aluminium, which can result in greater pore formation.
At voestalpine eifeler Lasertechnik GmbH, we have developed the laser cladding process to a point where it is able to generatively modify components with, for example, the powder material AlSi10Mg, or to improve the wear resistance of aluminium materials by applying various materials. This has significantly expanded the range of possible applications for aluminium materials.
The result of the process